The 2nd Commandment (Thou shalt not worship idols) was REMOVED from the Catholic "version" of the ten commandments, and the 10th split into two to get the total number back up to 10.
Here is an idol in the Basilica itself, that has been worshiped so much the bronze toes are worn smooth.
On this ancient bronze statue, St. Peter has his right toes worn down by centuries of pilgrims who traditionally kiss and touch the foot.
Here is the Christian version of the first two commandments:
And God spoke all these words, saying: “I am the Lord your God, who brought you out of the land of Egypt, out of the house of bondage.
1. You shall have no other gods before me.
2. You shall not make for yourself any carved image, or any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in the water under the earth; you shall not bow down to them nor serve them. For I, the Lord your God, am a jealous God, visiting the iniquity of the fathers on the children to the third and fourth generations of those who hate me, but showing mercy to thousands, to those who love Me and keep My commandments.
10.Thou shalt not covet thy neighbour's house, thou shalt not covet thy neighbour's wife, nor his manservant, nor his maidservant, nor his ox, nor his ass, nor any thing that is thy neighbour's.
Here are 1,2, 9 and 10 Catholic version:
1.I am the LORD thy God. Thou shalt have no strange gods before Me.
2. (Actually 3) Thou shalt not take the name of the LORD thy God in vain.
......
9.Thou shalt not covet thy neighbour's wife.(The Tenth Commandment is split into two to get back to Ten Commandments.)
10.Thou shalt not covet thy neighbour's goods.