The completely unselfish offering to God of one's good works and merits for the benefit of the souls in Purgatory rather than for oneself. Thus a person may offer to God for the souls in Purgatory all the good works he performs during life, all the indulgences he gains, and all the prayers and indulgences that will be offered for him after his death, such that he will be the last soul ever to be released from purgatory. The act is revocable at will, and is not a vow. Its actual ratification depends on the will of God.