Praying for the living and the dead is possible because of the truth of our Faith that we are part of the Mystical Body of Christ. So that this article will not be simply my own opinion, I will mention the Scriptures and the teaching of the Church on this matter. I could fill the page with Scripture quotes. Here are just a few.
Mt. 5:44 Pray for those that persecute you, for your enemies.
2 Cor. 13:9-10 What we ask in our prayers is for you to be perfect.
Col. 1:9 We have never failed to pray for you.
1 Thes. 5:25 Pray for us, brothers.
2 Cor. 1:11 You must all join in the prayers for us.
Catechism of the Catholic Church (CCC):
#789 The comparison of the Church with the body casts light on the intimate bond between Christ and His Church. Not only is she gathered around Him; she is united in Him, in His body. Three aspects of the Church as the Body of Christ are to be more specifically noted: the unity of all her members with each other as a result of their union with Christ; Christ as head of the Body; and the Church as bride of Christ.
#2635 Since Abraham, intercession – asking on behalf of another – has been characteristic of a heart attuned to God’s mercy. In the age of the Church, Christian intercession participates in Christ’s, as an expression of the communion of saints. In intercession, he who prays looks “not only to his own interests, but also to the interests of others,” even to the point of praying for those who do him harm.
As for praying for the dead…the Church has always taught us to practice this work of mercy. CCC #1030 – 1032. #1031 quotes St. Gregory the Great commenting on Mt. 12:31: “As for certain faults, we must believe that, before the Final Judgment, there is a purifying fire. He who is truth says that whoever utters blasphemy against the Holy Spirit will be pardoned neither in this age nor in the age to come. From this sentence we understand that certain offenses can be forgiven in this age, but certain others in the age to come.” Purgatory is a wonderful work of God’s mercy. Without it, we would either go to heaven or hell…no last chance to be purified in order to be able to live in God’s presence.
If we think for a moment, none of us came to know and love God without others praying for us…some of whom we will not know until we reach heaven. Because of this, we not only need to follow our Lord’s command to pray, but in a sense we owe it to others to pray for them, and this includes people that we just do not like.
So many people come to our door, call or write asking for prayers. It is a very important part of our lives, as Passionist contemplatives, to render this service to the Church. And it is such a joy, even though, as you can imagine, the great majority of these requests are about suffering. To bring the love of Jesus Crucified to hurting people is part of our vocation. It is not only our vocation, but one of the whole Body of Christ. We will do more by our prayers than we can even imagine, because they are united to God through Jesus Christ our Lord.