NO! Ask any Catholic, and they will tell you that they do not worship Mary or the Saints. It is easy to understand why people get confused, though, because many Catholics do pray to Mary and the Saints (many, but not all. I only pray to Jesus/God, for example). However, prayer is not the same as worship.
Let me clarify.
The Oxford Dictionary defines worship to be “reverence and adoration for a deity”. The only deity in Christianity (of which Catholicism is a part) is the Holy Trinity: God/Jesus/Spirit. To believe otherwise is not only unChristian, but it is also a violation of the Old Testament commandment: “You shall have no other gods before me.”
So if Catholics do not believe that Mary or the Saints are gods, why do they pray to them?
While Catholics do not believe Mary or the Saints are deities, they do believe that they are special. Mary was chosen by God out of all the women in history to be the mother of His son. The Saints were chosen in various ways to spread God’s love and Word, to suffer for Him, or to understand His nature beyond the normal call of humanity. To do this, God often invests these people with some of His powers. We see this in the Bible where after Jesus’ ascension, his disciples are given the power to speak in tongues, heal the sick, and perform other miracles. Catholics believe that death does not stop these people from doing God’s work, and that they are still able to help people from Heaven.
Now, naturally, if Catholics could pick up the phone and call Mary or the Saints for help, they would. But the phone bill for a call to Heaven is very, very expensive, so praying is the only way they know of to “talk” to people in Heaven. People have prayed in this way for ages. Anytime we “talk” to a deceased person as if they are really there and can hear us — whether we’re talking to them at a grave or looking at a picture, or just speaking into thin air — we are “praying” to them. Prayer is simply a channel of communication between someone alive on Earth, and someone who is not.
But why bother praying to Mary or the Saints for help in addition to praying directly to God/Jesus?
There are many instances in the Bible where God has made up His mind about something (such as destroying Sodom, or the Israelites, etc.) and His chosen people (e.g. Abraham, and Moses, respectively) successfully plead with Him not to. Exodus 33:17 states: “The LORD said to Moses, ‘I will also do this thing that you have spoken; for you have found grace in My sight, and I know you by name.'” And Jesus’ first miracle, turning water into wine, was done at Mary’s insistence, even though Jesus initially told her that “it was not yet time.”
So we see in the Bible many instances where God listens to certain people and will heed their requests, even against His initial decisions. And we see that to God, not everyone is equal in terms of His favor. For instance, in Numbers 12:2, Miriam and Aaron challenge, “Has the LORD indeed spoken only through Moses? Has He not spoken through us also?” and the Lord hears and gets angry at them and basically says that Moses is different, for he is the only one that God speaks to face-to-face.
Mary and the Saints are people similarly chosen to be close to God; they are people he has gifted with his Spirit and some of his Powers, that they might do his work in the world. Jesus could have, after His resurrection, chosen to stay on earth forever and walk among man saying, “Hey, look! I’m alive, I can heal your ills, I love you. Follow me and live!” but instead, he chose to delegate. He chose disciples to spread the Word for Him and gave them the gift of tongues and healing, of insight and understanding. They are his deputies, and He listens to them.
With all this in mind, many Catholics choose to pray to Saints/Mary for intercession with God — that is, they ask the Saints to pray for them to God. Matthew 18:20 says, “For where two or three come together in my name, there am I with them.” Clearly, there is power in numbers — simply one person calling out in God’s name is less powerful than two or three. Therefore, Catholics believe that although God will hear their prayers regardless, he will be more likely to heed them if more people are praying — especially if one of those people is someone whose requests He has been shown to heed in the past.
Occasionally, Catholics will pray to a Saint not for forwarded prayer to God, but for direct intercession in their lives — the cure of an incurable sickness, for instance. It is important to remember that they are not praying to Saints because they believe they are gods (they were people, after all), but because they believe that God has imbued them with certain powers and delegated to them certain tasks, whether it is the ability to care for the elderly, the sick, travelers, etc.
One way to think of this is like a corporation. God/Jesus is the CEO, and he has the power to handle any task he wants, and to listen to any complaint. Even so, he chooses managers to handle the concerns of the workers. While a worker with an issue could “go all the way to the top,” they generally prefer to deal with the manager first. With God and His Saints, Catholics have the advantage of getting to address their concerns both to God AND to his managers. Not only is the request coming from them now, but from those whom God has personally appointed to serve Him.
Perhaps as a Christian, you yourself prefer to go directly to “the top” where God is concerned. That is perfectly fine. I go directly “to the top” all the time. The point I want to make is simply that many Catholics also like going to God’s appointed managers. They know that these managers aren’t God, but they have influence with God. That is why they pray to Mary and the Saints.