For a Church doc, ready
Indulgentarium Doctrina (1967) by Pope Paul VI:*
This treasury also includes the truly immense, unfathomable and ever pristine value before God of the prayers and good works of the Blessed Virgin Mary and all the saints, who following in the footsteps of Christ the Lord and by His grace have sanctified their lives and fulfilled the mission entrusted to them by the Father. Thus while attaining their own salvation, they have also cooperated in the salvation of their brothers in the
unity of the Mystical Body.*Keyword search that document for “treasury” also to find additional references. Notice the emphasis on unity of the body, tying into what I said earlier about being joined to Christ’s body, the Church.
Here are some other related Scriptural examples I think apply:*Sirach 29:9-13 Help a poor man for the commandment’s sake, and because of his need do not send him away empty.
Lose your silver for the sake of a brother or a friend, and do not let it rust under a stone and be lost.
Lay up your treasure according to the commandments of the Most High, and it will profit you more than gold. Store up almsgiving in your treasury, and it will rescue you from all affliction; more than a mighty sheild and more than a heavy spear, it will fight on your behalf against your enemy.
Sirach 3:14 For
kindness to a father will not be forgotten, and against your sins it
will be credited to you.
Matthew 6:19-21 Do not lay up for yourselves treasures on earth, where moth and rust consume and where thieves break in and steal, but
lay up for yourselves treasures in heaven, where neither moth nor rust consumes and where thieves do not break in and steal. For where your treasure is, there will your heart be also.
Matthew 19:16-30 Jesus advises rich man to give to poor to acquire treasure in heaven.
Mark 10:21 (parallel of Mat. 19) And Jesus looking upon him loved him, and said to him, “You lack one thing; go, sell what you have, and give to the poor, and you will have treasure in heaven; and come, follow me.”
Proverbs 19:17 He who is generous to the dontrodden
makes a loan to the LORD; He will repay him his due.*Most of these quotes focus on treasury for the depositor (except for the Sirach 29 verse which also speaks of laying up treasure for one’s “brother”) but I think they all apply because they refer to acts of almsgiving and such and how that covers sin, is a “credit” or “loan” so to speak. Couple these with the other Scriptural examples above, and I think you have a good picture of the doctrine.