Words can be confusing when you want to define terms, and terms can be confusing when you want to define actions. Many concepts like “adoration, veneration, worship, reverence, homage, prayer and devotion”, though accurate to describe certain actions and ideas, lack a consistent use and meaning throughout history. When criticizing religious doctrines, such as the Catholic Marian dogmas, Protestants should use Catholic definitions and later compare such practices with those present in Scripture and history — just as they would expect us to use distinctions they do that we don’t consider biblical (e.g. sanctification vs justification, and regeneration vs baptism). This we do in order to avoid the ever changing nature of words to mud our study. An illustration of this is the word ‘worship’ itself, which in the Old English was simply used to describe any acknowledgement of worth, whereas nowadays has become a synonym to ‘adoration’.
Prominent Catholic figures like Augustine, Jerome and Aquinas explained in their writings the different senses in which Christians should honor God and creatures. The Catechism of the Catholic Church (CCC 2628) summarized their position and defines what we mean by “adoring”:
Adoration is the first attitude of man acknowledging that he is a creature before his Creator. It exalts the greatness of the Lord who made us and the almighty power of the Savior who sets us free from evil. Adoration is homage of the spirit to the “King of Glory,” respectful silence in the presence of the “ever greater” God. Adoration of the thrice-holy and sovereign God of love blends with humility and gives assurance to our supplications.
As for the latria, hyperdulia and dulia distinction, the Church states the following:
«The special veneration due to the Blessed Virgin Mary. It is substantially less than the cultus latria (adoration), which is due to God alone. But it is higher than the cultus dulia (veneration), due to angels and other saints. As the Church understands the veneration of Mary, it is to be closely associated but subordinated to that of her Son. “The various forms of piety towards the Mother of God, which the Church has approved within the limits of sound and orthodox doctrine according to the dispositions and understanding of the faithful, ensure that while the mother is honored, the Son through whom all things have their being and in whom it has pleased the Father that all fullness should dwell, is rightly loved and glorified and His commandments are observed”» 
In the end, the way a Christian honors or worships (in the old-fashioned sense of the word), can be broken down as follows:
Once confronted with such a clear doctrinal distinction, many have attempted to argue from Scripture that such distinction is unbiblical, though without success. Such is the case of James White, who insists the Bible condemns any type of intercessory/petitionary prayer, service and veneration in a religious context when such actions are not addressed to God. In the end, White’s argument is a modified version of what Calvin argued in his Institutes , but instead of focusing in the Greek, White focuses in the Hebrew text. Others  have addressed such type of reasoning more specifically, so I won’t take the time to go over his arguments; only those that happen to overlap with Matt Slick’s article “Do Catholics Worship Mary?”.
According to Slick, the biblical way in which the people of God pay their homage to God alone is by:
■ setting up altars,
■ bowing down,
■ being devoted to,
■ entrusting one’s self to,
■ celebrating feasts to,
■ giving glory to,
■ having locations of (?),
■ looking to,
■ praying to,
■ and/or worshipping.
There is a fundamental flaw in this interpretation. Both Protestants and Catholics will agree that these actions in and of themselves are not sins. They only become sinful if the recipient of some of these actions is someone other than God. Some actions are owed to God alone, like adoring or setting up sacrificial altars; while others, like bowing down, can be performed towards human beings without any guilt. Let’s analyze some of these controversial actions:
Not surprisingly, in Slick’s article there was only an image to argue that Catholics adore Mary. Never in the history of the Church has the Magisterium officially taught or produced a document inviting Catholics to adore Mary in the same way we adore our almighty God. The challenge to produce such evidence has been laid out many times, and Protestant apologists have continuously neglected such proof. Old pious prayers with archaic lofty and exalted language won’t suffice as evidence.
The accusation that Catholics built altars to worship Mary is a common misunderstanding of ancient architecture. Due to their scale, Romanesque and Gothic layouts in churches would allow certain subdivision of interior spaces, also known as chapels, to allow the building to host more than one activity at a given time — even different masses at a time. In big churches like basilicas and cathedrals, these chapels, yet part of the larger apse, would be often be considered separate from the larger main layout. Chapels would often be dedicated to certain persons of the Trinity, saints, angels or even patrons; and some of them would be equipped with altars to celebrate the Holy Sacrifice of the Eucharist in a smaller scale, with a smaller crowd. The sacrifices taking place in these secondary altars were never offered to the saint or angel to whom the chapel was dedicated, for that matter, the offers were not directed towards the surrounding images or statues. As explained, these spatial arrangements allowed for the personal devotions to these heroes of the faith to be more intimate, and to manage the crowds when the need arises.
Altar sacrifices should indeed be offered to God and to God alone. Bishop Epiphanius of Salamis in his Panarion denounces the heresy of the Collyridians, who pretended to offer quasi-Eucharistic sacrifices to the Virgin Mary. The group was immediately condemned and classified as a heresy by the Early Church. This only reaffirms the ecclesiastic commitment to offer the Holy Virgin proper veneration, and it confirms the always-present understanding that the Eucharist was the ultimate pleasing-to-God memorial sacrifice. It is worth to note Epiphanius was one of the few Church Fathers who was somewhat scandalized to some early Christian practices that involved the decoration of churches with images and statues of the saints. Again, this only proves it was already common by the time he wrote about this issue.
One of the earliest Christian prayers, the Sub tuum praesidium (c. 300 AD), reads as follows: “We fly to thy patronage, O holy Mother of God; despise not our petitions in our necessities, but deliver us always from all dangers, O glorious and blessed Virgin. Amen.” Entrusting ourselves to the care of angels and saints, and entrusting them with our petitions through the power of the Holy Spirit, so that they intercede before the Father, is not unbiblical. The book of Revelation portrays angels and saints in Heaven, receiving the prayers of the holy ones here on Earth, and presenting them to the Father (Rev 5:8, 8:3-4*).
Additionally, the Catechism teaches:
The Holy Spirit who teaches the Church and recalls to her all that Jesus said also instructs her in the life of prayer, inspiring new expressions of the same basic forms of prayer: blessing, petition, intercession, thanksgiving, and praise. 
The petitions in which we mention Mary’s role are primarily prayers of intercession…:
Since Abraham, intercession – asking on behalf of another has been characteristic of a heart attuned to God’s mercy. In the age of the Church, Christian intercession participates in Christ’s, as an expression of the communion of saints. In intercession, he who prays looks “not only to his own interests, but also to the interests of others,” even to the point of praying for those who do him harm.
The first Christian communities lived this form of fellowship intensely. Thus the Apostle Paul gives them a share in his ministry of preaching the Gospel but also intercedes for them. The intercession of Christians recognizes no boundaries: “for all men, for kings and all who are in high positions,” for persecutors, for the salvation of those who reject the Gospel. 
… and prayers of petition:
Christian petition is centered on the desire and search for the Kingdom to come, in keeping with the teaching of Christ. There is a hierarchy in these petitions: we pray first for the Kingdom, then for what is necessary to welcome it and cooperate with its coming. This collaboration with the mission of Christ and the Holy Spirit, which is now that of the Church, is the object of the prayer of the apostolic community. It is the prayer of Paul, the apostle par excellence, which reveals to us how the divine solicitude for all the churches ought to inspire Christian prayer. By prayer every baptized person works for the coming of the Kingdom. 
Though the latter type of prayer is not as common when it comes to the figure of Mary, it is still valid to invoke her name in such manner. E.g. “Father in Heaven, in your mercy, grant me the virtues you entrusted to your servant Mary; so that with your graces I may be equipped to …”. Mary, ultimately aligns the prayer of Christians and God’s servants to “do whatever He tells you” (Jn 2:5). Let us remember James’ words (5:16): “the prayer of a righteous man is powerful and effective”; how much more effective will the intercession of the Mother of God be?
As preamble, Romans 14:5-6 invites Christians to avoid passing judgment over those converts who observe Jewish feasts. The context of the passage is denouncing the criticism that people whose faith is stronger have towards those Jewish converts whose faith is weaker. Paul argues that the important thing is to live for the Lord, and that’s what Catholics are called to and constantly reminded of.
Exodus 32:5 is quoted as somehow prohibiting all types of feasts. The reality is that the Bible does not forbid the celebration of non-biblical feasts. The Jews did not take it that way either. Until this day, most of them have observed the Feast of the Dedication, which Slick would probably consider unbiblical, sourced in the victory of the troops of Judas Maccabeus over the Macedonian rulers and the purification of the new temple. Some people even argue that Jesus Himself used this feast to come into the world as the true new temple. Similarly, other Jewish feasts celebrate God’s work with His people, which is the whole point of having feasts in the Church as well. When the Church celebrates someone’s feast, it primarily celebrates God’s work on his loyal servant(s). Mary is the most excellent creature that ever existed, so naturally the Church celebrates her with special consideration.
Here is where the Reformed idea of monergism becomes more apparent. We do not take away glory from God when the Body of Christ is exalted by God’s own power. The strange view that members of the Body of Christ should not have any sort of glory has crept into the Church; perhaps not acknowledging that God works in us by endowing us with His own glory. The Father conferred glory to His incarnate Son, so He may confer it to us (John 17:22). He raises us up to have us seated in Heavenly places (Ephesians 2:6), where we will judge angels (1 Corinthians 6:3) and the twelve tribes of Israel (Matthew 19:28, Luke 22:30), and reign with Him if we endure (2 Timothy 2:12) and suffer in his name (Romans 8:17). All this, so that by following His Gospel, we may gain His glory (2 Thessalonians 2:14).
Our God is not a jealous one in this sense, He is a God that shares in His glory, by making us participants in the divine nature (2 Peter 1:4). Therefore, we do not err when we promote the God-given glory of Mary, for this is not of her own doing; but conferred by the Lord Himself. There is a difference between acknowledging the glory of a person who has lived a godly life, and conferring a glory we don’t have via a power we don’t have, since the latter is impossible.
I recall two common instances in the Bible in which creatures have been rebuked by kneeling/bowing down to other creatures. In Acts 10:25-26, Cornelius, having little knowledge of the Christian faith, is warned by Peter not to prostrate himself before him. In Revelation 19:10, and Revelation 22:9, John can’t resist the temptation to adore the angels of God. As a sidenote, in Tobit 12:16, we have no indication that angels are displeased when humans fall to the ground before them out of fear without the intention to worship; in fact they bring consolation to help overcome that fear. We see then; bowing down, prostrating, kneeling or falling to the ground, is only considered sinful when our intention is to worship/adore the creature or idol in front of us.
We have a better and more accurate biblical analogy we should study when it comes the Blessed Mother. In 1 Kings 2, we have the Gebirah, the “Great Lady” (a typos of Mary), approaching King Solomon (a typos of Jesus). As you would imagine, this queen lady is Bathsheba, the mother of the king. In verse 19, she enters where the king is seated to intercede for Adonijah, and the king Solomon “stood up to meet her, bowed down to her and sat down on his throne”. Having bowed before King David in chapter 1:31, she now receives this level of reverence from her own son. Make no mistake, Mary is indeed the cosmical Gebirah (Rev 12:1), and as the great intercessor, we should treat her with the same level of respect.
In Joshua 7:6, Joshua fell face-down before the Ark of God. Did the Israelites adore the Ark? No, but they paid utter reverence to it because it signified God’s presence. Otherwise the Ark would have faced the same fate as the Nehushtan did. In the same fashion, Mary is the New Ark of the Covenant. She contained the Word of God in flesh, as the Ark contained the Word of God in stone; she contained the Living Bread from Heaven, as the Ark contained the heavenly Mana; and she contained the true High Priest, as the Ark contained Aaron’s rod, symbol of the priesthood. Even fake idols fell down in prostration with their heads crushed before the Ark (1 Samuel 5:4), just as Mary’s seed is promised to crush the head of the serpent and her offspring in Genesis 3:15.
All things considered, we have learned that worship in the Christian faith and Catholic theology encompasses different levels of respect; and though contemporary linguistic considerations would favor terms like veneration instead, there is no theological error in saying worshiping someone, in the traditional sense of the word, is a sinful practice. When ‘adoring’ is used as a synonym of ‘worship’, and such practice is oriented towards a creature, idol or interest, it is always sinful as it does fall into the category of idolatry.
The Reformers were tough critics of this distinction of latria and dulia, yet they had to say the following about Mary:
“The veneration of Mary is inscribed in the very depths of the human heart.”
In his last Sermon at Wittenberg, in January 1546 he preached:
“Is Christ only to be adored? Or is the holy Mother of God rather not to be honoured? This is the woman who crushed the Serpent’s head. Hear us. For your Son denies you nothing.”
In his 1531 sermon at Christmas, while strongly arguing the Catholic devotion to Mary detracted from Christ, Luther wrote:
“[…] what are all the maids, servants, masters, mistresses, princes, kings, and monarchs on earth compared with the Virgin Mary, who was born of royal lineage, and withal became the mother of God, the noblest woman on earth? After Christ, she is the most precious jewel in all Christendom. And this noblest woman on earth is to serve me and us all by bearing this child and giving him to be our own! […] True it is, she is worthy of praise and can never be praised and extolled enough. For this honor is so great and wonderful, to be chosen before all women on earth to become the mother of this child.”
“I esteem immensely the Mother of God, the ever chaste, immaculate Virgin Mary”.
He later goes on to say: “The more the honor and love of Christ increases among men, so much the esteem and honor given to Mary should grow”.
Calvin — from whom a famous Reformed Protestant said: “Among all those who have been born of women, there has not risen a greater than John Calvin”  — coincidently said:
“It cannot even be denied that God conferred the highest honor on Mary, by choosing and appointing her to be the mother of his Son.”
He again wrote: “To this day we cannot enjoy the blessing brought to us in Christ without thinking at the same time of that which God gave as adornment and honour to Mary, in willing her to be the mother of his only-begotten Son.”
This same honor we Catholics promote and proclaim, this is the honor we Catholics celebrate; for “all generations shall call her blessed” (Luke 1:48).
* Tobit 12:12 supports the role of angels and archangels as the ones who present the prayers to God.
 Merriam Webster Dictionary (online).
 The City of God, Book X.
 Letter 109, Paragraph 1.
 Summa Theologica, 2nd II, Q 103, Arts 3 & 4.
 Second Vatican Council, Lumen Gentium, VII, 66.
 Institutes of the Christian Religion, 1:12:2.
 The Panarion of Epiphanius of Salamis, Books II and III. De Fide. Nag Hammadi and Manichaean Studies (Second, revised ed.). 79. 2012-12-03 – via Brill.
 Catechism of the Catholic Church (CCC 2644).
 Ibid. 2635, 2636.
 Ibid. 2632.
 Martin Luther, Weimar edition of Martin Luther’s Works (Translation by William J. Cole) 10, p. 268.
 Martin Luther, Weimar edition of Martin Luther’s Works
 Martin Luther, Sermon at Christmas (1531), Luther’s Complete Sermons Vol. 5 Ed. by George Roerer (14-15).
 E. Stakemeier, De Mariologia et Oecumenismo, K. Balic, ed., (Rome, 1962), 456.
 Ulrich Zwingli, Zwingli Opera, Corpus Reformatorum, Volume 1, 427-428.
 C. H. Spurgeon, Autobiography, Vol. II: The Full Harvest
 John Calvin, Calvini Opera [Braunschweig-Berlin, 1863-1900], Volume 45, 348.” Page 348
 John Calvin, A Harmony of Matthew, Mark and Luke (St. Andrew’s Press, Edinburgh, 1972), p.32.