Often, people who have lost a loved one are encouraged to pray for those who have passed away and for their families. Of course, we should pray for those grieving, but for the dead, no. No one should ever believe that someone may be able to pray for him, thereby effecting some kind of favorable outcome, after he has died. The Bible teaches that the eternal state of mankind is determined by our actions during our lives on earth. “The soul who sins is the one who will die. . . . The righteousness of the righteous man will be credited to him, and the wickedness of the wicked will be charged against him” (Ezekiel 18:20).

The writer to the Hebrews tells us, “Just as man is destined to die once, and after that to face judgment” (Hebrews 9:27). Here we understand that no change in one’s spiritual condition can be made following his death—either by himself or through the efforts of others. If it is useless to pray for the living, who are committing “a sin that leads to death” (1 John 5:16), i.e., continual sin without seeking God’s forgiveness, how could prayer for those who are already dead benefit them, since there is no post-mortem plan of salvation?

The point is that each of us has but one life, and we are responsible for how we live that life. Others may influence our choices, but ultimately we must give an account for the choices we make. Once life is over, there are no more choices to be made; we have no choice but to face judgment. The prayers of others may express their desires, but they won’t change the outcome. The time to pray for a person is while he or she lives and there is still the possibility of his or her heart, attitudes, and behavior being changed (Romans 2:3-9).

It is natural to have a desire to pray in times of pain, suffering, and loss of loved ones and friends, but we know the boundaries of valid prayer as revealed in the Bible. The Bible is the only official prayer manual, and it teaches that prayers for the dead are futile. Yet we find the practice of praying for the dead observed in certain areas of “Christendom.” Roman Catholic theology, for example, allows for prayers both to the dead and on behalf of them. But even Catholic authorities admit that there is no explicit authorization for prayers on behalf of the dead in the sixty-six books of canonical Scripture. Instead, they appeal to the Apocrypha (2 Maccabees 12:46), church tradition, the decree of the Council of Trent, etc., to defend the practice.

The Bible teaches that those who have yielded to the Savior’s will (Hebrews 5:8-9) enter directly and immediately into the presence of the Lord after death (Luke 23:43; Philippians 1:23; 2 Corinthians 5:6, 8). What need, then, do they have for the prayers of people on the earth? While we sympathize with those who have lost dear ones, we must bear in mind that “now is the time of God’s favor, now is the day of salvation” (2 Corinthians 6:2). While the context refers to the gospel age as a whole, the verse is fitting for any individual who is unprepared to face the inevitable—death and the judgment that follows (Romans 5:12; 1 Corinthians 15:26; Hebrews 9:27). Death is final, and after that, no amount of praying will avail a person of the salvation he has rejected in life.

http://www.gotquestions.org/praying-for-the-dead.html#ixzz3dF19BMrv