[Dr. Eckleburg]

Mary and the Saints, because of their faithfulness to God and their good works have added to the Treasury of Grace. The impression I got from reading that is that Mary and Saints added a limited amount to the eternal Treasury of Grace that we have access to.

That opinion is anti-Scriptural;. There is nothing in the Bible about Mary or anyone else "adding to the Treasury of Grace."

However there is plenty of Scripture which tells us Christ alone redeems His flock.

"(God) who hath delivered us from the power of darkness, and hath translated us into the kingdom of his dear Son:

In whom we have redemption through his blood, even the forgiveness of sins:

Who is the image of the invisible God, the firstborn of every creature:

For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him:

And he is before all things, and by him all things consist." -- Colossians 1:13-17

[Petronski]

There is nothing in the Bible about Mary or anyone else "adding to the Treasury of Grace."

There is nothing in the Bible mandating sola Scriptura.