Seeing Catholics kneeling in prayer before images of Jesus and the Saints causes some to fear that Catholics are committing idolatry, but that fear is based on a misguided interpretation of Exodus 20:4.
Éxodo 20:4 doesn’t prohibit the making of images, por sí mismo, but worshipping of the images as gods (see Exodus 20:5).
Consider that God Himself ordered the Israelites to make statues of cherubim for the Ark of the Covenant and a bronze serpent mounted on a staff (ver Éxodo 25:18-20, el Libro de los Números 21:8-9, o el First Book of Kings 6:23 & 7:25).
While the Israelites revered these objects, they did not worship them for they refrained from offering sacrifices to them. (The molten calf of Éxodo 32:5-7, sin embargo, to which sacrifice was offered is another matter!)
The fundamental difference between a devotional image and an idol is that the former is considered to be a picture of God or a holy person while the latter is actually thought to be (and worshipped as) a deity. No right-minded Catholics believes a statue or fresco or painting or jpeg is God.
Catholic religious images are merely reminders of God and the Saints, which are helpful in prayer and worship. Así, to repeat, no Catholic worships the actual images or statues as gods, but we do appreciate the beauty that artists, who have been divinely inspired, have created for us–many which grace these pages.