Answer
In Roman Catholicism, the treasury of merit is the super-abundant store of righteousness and good works belonging to Christ, the Virgin Mary, and the saints. The treasury of merit is filled with the merit of Christ and Mary (who were sinless), and the saints, who had more than enough merit to enter heaven themselves—they had earned more spiritual rewards than they needed. This merit is now available to others to “supplement” their own meritorious works.
According to Rome, just a drop of Christ’s blood would contain enough merit to save the whole world, so the excess blood Christ shed on the cross was stored in a treasury of merit in heaven. Of course, the Bible says nothing about the number of drops of blood Christ shed or how many were sufficient for salvation. The emphasis in the Bible is not on the physical volume of Jesus’ blood but on the act of sacrifice. Jesus’ blood was spilled to fulfill the Old Testament requirement for blood sacrifices so that such sacrifices were no longer necessary (Leviticus 17:11; Hebrews 9:11–18).
Catholic doctrine teaches that not only is the excess of Christ’s meritorious work stored in the treasury of merit, but also the righteous works of Mary and other saints. Mary, Catholicism maintains, was sinless, and she gained far more merit than what she needed for entrance into heaven, and so her “extra” merit was added to the treasury. According to the Catechism of the Catholic Church, “This treasury includes as well the prayers and good works of the Blessed Virgin Mary. They are truly immense, unfathomable, and even pristine in their value before God. In the treasury, too, are the prayers and good works of all the saints, all those who have followed in the footsteps of Christ the Lord and by his grace have made their lives holy and carried out the mission in the unity of the Mystical Body.”
The philosophy behind the treasury of merit is entirely unbiblical. In fact, the idea is the very opposite of the teachings of Christ and the apostles. To begin with, the Catholic view that people can get into heaven if they do sufficient good things essentially eliminates the need of a Savior. If some people have much more merit than they actually need to get into heaven, then it follows that it is meritorious works, and not grace, that are the basis of salvation. But Ephesians 2:8–9 states, “It is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God—not by works, so that no one can boast.”
No one enters heaven on the basis of his own merit. The Bible clearly teaches that “a person is not justified by the works of the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by the works of the law, because by the works of the law no one will be justified” (Galatians 2:16). See also Romans 3:20–27.
Furthermore, the idea that Mary was sinless and her good works could thus be transferred to others denies clear scriptural teaching. Paul was emphatic on this subject: “For all have sinned and fall short of the glory of God” (Romans 3:23). He did not say “all have sinned except Mary.” He said “all”; everyone, each person, is a sinner. He also said, “There is no one righteous, not even one” (Romans 3:10; cf. Psalm 14:3). The “no one” includes Mary. Mary herself acknowledged this truth, i.e., that all have sinned and are in need of a Savior. She declared, “My spirit rejoices in God my Savior” (Luke 1:47, emphasis added). Not only did Mary not have sufficient merit to get others into heaven, she didn’t have enough merit to get herself into heaven! That is why she rejoiced in her “Savior.”
Perhaps most egregious of all, Roman Catholicism teaches that the treasury of merit is placed under the charge of the Pope, who alone possesses the power to dispense merit at his discretion through what are called “indulgences.” He can take merit from the treasury of merit and apply it to those who can then get closer to heaven than they could with their own merits. Historically, the Roman Church allowed people to buy this merit by, for example, donating money for important church projects. Buying indulgences from the treasury of merit could also be applied to those in Purgatory in order to shorten their time there. It was the selling of indulgences that angered Martin Luther and others. Thus, the concept of a treasury of merit was part of what brought about the Protestant Reformation.