Speaking of people here on earth... mentions nothing about contacting the dead which is necromancy.
Some object that the Catholic position on intercessory prayer is the same as necromancy, that is, calling upon the spirits of the dead to find out the future or obtain other information.
Necromancy is a grave sin that, far from fostering communion, shows a lack of faith and trust in God. Necromancy was punishable by death under the Mosaic law (Lev. 19:31, 20:6). Some of the early Israelites practiced necromancy, including Saul (1 Sam. 28:3, 8-14), and they were punished severely for doing so (1 Sam. 28:17-19). This practice offended God (2 Kings 21:6) and led to the destruction of Israel.
Catholics do not practice necromancy, which is explicitly forbidden by the Church (cf. Catechism, nos. 2115-17). Rather, they ask for the prayers of the saints to foster communion in the Family of God.
Seeking the intercession of the saints is not necromancy for two reasons:
First, necromancers are usually trying to receive information that they do not have, such as what will happen in the future. Asking the saints to pray for us, however, is not a form of divination or fortune telling.
Second, necromancers are also trying to bring back and control the souls of dead people. Catholics, on the contrary, believe that those who have died in God’s grace are not dead but truly alive, and are able to help us by their prayers. As Jesus says, “[Moses] calls the Lord the God of Abraham and the God of Isaac and the God of Jacob. Now he is not the God of the dead, but of the living; for all live to him” (Lk. 20:37-38).
According to Jesus, death cannot separate the faithful—such as Abraham, Isaac, and Jacob—from God. And, if they are alive to God, they must be alive to us through Him as members of His one body. Otherwise, contrary to what Saint Paul says, Christ’s victory over death was incomplete, and His body is not truly one (cf. Jn.17:21; 1 Cor. 12: 12,13; 15:14 et al).
Catholics agree necromancy is prohibited. The difference in communion of saints is the source of the supernatural power and the intention.
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