Catholics worship God alone. It is important that we make this clarification at the outset. Any homage or honor shown to saintly men and women who have died before us is not the same as the worship and adoration given to the Father, Son, and Spirit – the Trinitarian God in whom all Christians believe.
The technical Latin terms used to express this difference are:
latria - which is the adoration or worship given only to God, in Whom we place our whole being as He is our Creator, our Redeemer, and our Sanctifier)
dulia - which is the honor and respect we show to the Saints, fellow humans who have achieved their Heavenly reward and are now in the presence of God.
All Christians including Catholics give latria/worship to God. But most Protestants/non-Catholics do not engage in dulia/honor shown to the Saints. The reasons for this are many, but from a Protestant perspective the answer seems simple: the Catholic practice is unbiblical and therefore either un-necessary or even blasphemous or idolatrous.
To answer this charge, we may find it simpler if we divide the issue into parts and answer each individually. As suggested by the wording of the question above, we can look at three aspects of the Catholic practice: 1) saints in general, 2) the uniqueness of Mary, and 3) the use of statues, carved images and iconography. In the end, we will see that the Catholic practice of praying to saints and Mary and the use of images is not only acceptable but has a biblical basis.
1) The Catholic practice of ‘praying’ to Saints
Since Catholics are not “worshipping” saints, then what exactly are they doing when they “pray” to those who have died? Can the dead hear us, and do they even take an interest in what is happening here on earth?
We know that the dead can hear us, and that they are engaged in what is happening in our lives, because the Bible gives us examples of this. In Jesus’ own life we see Him converse with the dead during the transfiguration:
“And while he was praying, the appearance of his face changed, and his clothes became dazzling white. Suddenly they saw two men, Moses and Elijah, talking to him. They appeared in glory and were speaking of his departure, which he was about to accomplish in Jerusalem.” (Luke 9:29-31)
Now, Catholics do not expect a miraculous apparition, a vision, or a verbal response to our prayers when we pray to the saints. What we do expect and hope for is that the saints in Heaven will go to God on our behalf and speak to Him, as Moses and Elijah spoke to Jesus, and that they will pray with us for whatever intention we wish to lay before God.
In Scripture we read that “the prayer of the righteous is powerful and effective.” (James 5:16) Those who have died and are in Heaven are certainly “righteous.” When we “pray to” Saints, what we mean is that we “send our prayers up to them” and ask that they make our prayers their own. Just as we would ask our friends and neighbors here on earth to pray for us, so too, we ask our Christian family and friends in Heaven to join us in prayer.
Even so, we know that our prayers will only be answered if God allows it. The saints do nothing apart from God. In the transfiguration, Moses and Elijah appeared only because the Father allowed them to appear. The Apostles who witnessed this event were granted that vision as a part of God’s plan, not the plan of Moses and Elijah. God can allow or deny such intercession from the dead as He sees fit. (The story of the rich man and Lazarus in Luke 16:19-31 might be an interesting passage to reflect upon in this regard. But in contrast we might read Matthew27:53, immediately after the Resurrection, where we see the dead participating in God’s glory: “They came out of the tombs, and after Jesus' resurrection they went into the holy city and appeared to many people.”)
Since the Bible tells us of these miraculous happenings, we can be certain that the dead are alive in God, since He is “the God of the living” (Matthew 22:32), and that the Saints do participate actively in God’s plan. Most assuredly they bring our prayers before God’s throne. In Revelation John tells us that our prayers are brought before God by those in His “Heavenly Court”:
“…the four living creatures and the twenty-four elders fell down before the Lamb. Each one had a harp and they were holding golden bowls full of incense, which are the prayers of the saints.” (Revelation 5:8)
In fact, Revelation is filled with scenes of Heavenly worship, in which those who have died together with the Angels offer praise, worship and petitions before God. Since we know this to be true, then it only makes sense that we should offer our prayers to the Saints and Angels so that they can add their voices to our own.
2) The uniqueness of Mary
To explain the role of Mary in Catholicism would take more space than what I have here, so I will be brief…
If Catholics offer honor and respect to the Saints in the form of dulia, then we offer a heightened form of honor to Mary which is called hyperdulia. This is because Mary played such a unique role in salvation history. If the Saints are honored because they participate in God’s plan and they show forth His grace and love in their lives, then Mary does so beyond compare. She is the Mother of God, the Theotokos (God-bearer), the New Eve (to Jesus’ New Adam), she is the woman of Revelation with twelve stars on her head, clothed in the sun, and the moon at her feet. This woman was taken to a special place prepared by God and protected from the dragon (Revelation 12:6). Mary thus holds a special place for Catholics, because we see it reflected in Scripture.
No other woman bore God in her womb and raised God as her own child. If Jesus is our spiritual brother, then Mary is our spiritual mother. She is not equal to God; we do not worship her. But she points the way to God: “Do whatever he tells you.” (John 2:5) Her “yes” to God won us a Savior. We love her as any good son would love his mother, and we do this in imitation of Christ: “Behold your mother.” (Luke 19:27) We fulfill the words she spoke of herself: “all generations will call me blessed” (Luke 1:48)
(Any further questions about Mary ought to be dealt with individually…)
3) The use of statues and other images
Now the charge of idolatry can be discounted rather easily. As I already clarified, latria and dulia are distinct. Catholics are not worshiping the saints – we are not expecting the saints to save us or to pour out graces or blessings of their own. They are people just like us and are subordinate to God.
Then why the statues, paintings, and stained glass?
As I said before, we honor the Saints as we would any great hero of the past. We erect statues and monuments for our secular leaders (Presidents, war heroes, the Founding Fathers) and we make trips to these monuments so that we can pay our respects, remember their accomplishments, and revel in history. Our children learn from these physical reminders of our past.
We even erect memorials to lesser figures, such as the tombstones we place at the gravesites of our loved ones. We adorn these sites with flowers and mementos; we engraved images on them and messages of hope and love. We spend time at these monuments silently pondering the meaning of their life and death.
No one worships a tombstone. No one worships George Washington. But we place these physical reminders in special places to remind us of what came before us. And we spend time at these places to collect our thoughts and focus our attention at that one moment in time. This is what Catholics do when we place statues and other artistic objects in our churches depicting the Saints and Christ.
(The use of art and imagery in worship is not foreign to the Bible. There are references to artistic expression in the Old Testament, for instance the angelic images that surrounded the Ark of the Covenant as ordered to be constructed by God in Exodus 25. As long as these images are not worshipped as gods then it is not idolatrous.)
The Saints are our family…
When someone says, “My mother died when I was very young, but I know that she still looks over me from Heaven,” or “My grandfather passed away years ago, but I still feel his presence, and find comfort in knowing that he is with me,” that is the way Catholics feel about all the Saints. The Saints are our family because we are all God’s children. The Bible tells us that those who died in Christ are alive in Christ and they intercede on our behalf; they offer our prayers as incense before God. Catholics recognize this Biblical truth and put it into practice.