Adoration is offered only to God and veneration is given to saints. No Catholic adores or venerates a statue. Statues are used only as symbols to invoke the presence of God or saints. The photographs of our deceased parents and the portraits of our great leaders invoke their remembrance in us and the great sacrifice they have done for our welfare. By establishing photos and portraits, we don't honour a piece of paper or a quantum of metal, but the persons represented by them. So also in the case of religious statues. Somehow the invisible is to be presented to the visibility of man. But one shall not mistake the signs used for the reality itself.
In Ex. 20:3-5, we read, "You shall have no other Gods before me. You shall not make for yourselves any carved image, or any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in water under the earth. You shall not bow down to them and serve them. For I am the Lord your God." This command is to be evaluated in the pagan background. The pagans had thousands of Gods which had the form or anything in heaven, on earth and in water. They used to make their statues and adore them. But Israel believed in the one God, their liberator God. It is only after a long history that people finally come to the belief of one God. However Israel was blessed to come to this belief sufficiently earlier, since God himself revealed it to them. Hence, to prevent the pagan influence of polytheism on their monotheism, it was necessary to issue strict sanctions against idol-worship. This command holds good today if and when the idols are made for worship.
But the idol has only a sign value, and is not worshipped. It need not be discouraged. Because man needs such signs and symbols. Even in OT, the presence of Yahweh is made visible and audible by the thick cloud (Ex. 19:7), thundering and lightening ( V 16), and fire (V 18). He asks Moses to build him a sanctuary to dwell among his people (Ex. 25:8), and to make an ark to keep his Testimony (convenant stipulations, the Ten Commandments). He also asks Moses to make a Mercy seat with two cherubim at the two ends and place it over the Ark of the Convenant (W 17-21). It is on this Mercy seat that the invisible Lord of Mercy (Ex. 20:6) will meet his people (Ex. 25:22). We know that the Ark, the stone, the tablets, cherubim, and mercy seat have little value in themselves. However they are powerful symbols of Israels' God experience.
In Num. 21 :6-9 we find. the Lord asking Moses to "make a fiery serpent, and set is on a pole" so that every one who is bitten (by serpents) may be saved when they look at it. Moses did as the Lord commanded, and everyone, who looked at the bronze serpent, lived ( V 10). However it is clear that it was not the fiery serpent that saved them, but the Lord (Wis. 16:7-8). Fiery serpent was only an instrument in God's saving act.
T prohibits idol-worship (1 Cor 8:4) because we have only one God (V 6). Catholics are not idol-worshippers. For us statues and symbols are powerful symbols only - Symbols of Christ's and his saints' presence. No statue works miracle, but only God. God who used the statue of a serpent (Num 21:10), a garment (Mt 9:20-26), handkerchief, apron etc (Acts 19:12) to work miracle, could use even statues, scapulars, pictures and relics to work miracles. But God would certainly punish if these pious articles are adored thinking that they have power by themselves (Cf. 2 kgs. 18:4) Neither any artist or his artistic work is to be condemned, because it is the Lord who has filled the artist with the spirit of God, in wisdom, in understanding, in knowledge and in all manner of workmanship to design artistic works (Ex. 31 :3-6). What is to be corrected is the wrong notion regarding the power of the man made artistic works.