Where does it say that?

Protestants often wonder why Catholics pray for the dead.   Most Protestants are not aware that Martin Luther, a heretic Catholic priest, tore out the two books of Maccabees from the Bible.  Therefore, Protestants are not aware of the story of Judas praying for his fallen comrades, and they ask where in the Bible is a description of Purgatory. 

On All Souls Day, the Catholic Church offers prayers and liturgies for the repose of the dead. As Catholics, we are called by the Church to focus our spiritual energies to assist these poor souls, who, though saved, are still in need of purification. Our prayers and sacrifices assist them in this process of purification as a means used by God to communicate purifying grace to them. After all, He is the vine, we are the branches so that He produces his fruits of grace through us. 

The practice of praying for the dead actually predates Christianity. In 2 Maccabees 12: 41-45, Judas offers prayers and sacrifices for his fallen comrades to make “atonement for the dead that they might be absolved from their sin.” Some argue that the books of the Maccabees are not inspired scripture. Leaving that argument aside for now, we can at least look at them as historical books detailing accepted pious practices of God’s people some 300 years before Christ.

If that is the only place in the Bible where we find any reference to purgatory, many Protestant Christians argue, then that is a weak support for such a practice. Fortunately, we know as Catholics that all of our doctrines are indeed found in the Word of God, as is the doctrine of Purgatory. Hence what follows is a biblical understanding of the Catholic doctrine of Purgatory.

The book of Genesis recounts for us the far reaching repercussions of Adam and Eve’s disobedience in the Garden. This sin, we find, brought about four consequences which I will summarize here (Gen 3: 16-24):

First, their sin brings about disharmony between persons. God tells Eve that both her relationship to her husband and children will now be characterized by pain and mistrust (Gen 3:16). Further, God has to make garments for man and woman because now, as the text implies, they feel shame (Gen 3:21).

Second, their sin brings about disharmony between man and creation. God tells Adam that he will produce the fruit of the earth with toil and difficulty (Gen 3: 17). Even the ground itself is cursed because of their sin (Gen 3: 17).

Third, their sin brings about disharmony between man and himself. He no longer has spiritual control over his body; thus, his body returns to the dust of the ground (Gen 3: 19). Adam and Eve are no longer able to receive everlasting life (Gen 3: 22).

Lastly and most importantly, sin brings disharmony between God and man. This consequence results in mistrust and fear of God (Gen 3: 10), and, worse, spiritual death. Without God, neither physical nor spiritual life can be sustained (Gen 3: 19, 24).

http://www.prayerandperspective.com/2014/10/all-souls-purgatory-and-the-bible/