For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; Ephesians 2:8
The third cry that formed the reformers faith statement was that of “sola gratia.”
This ‘sola’ was necessary in the fifteenth and sixteenth century owing to how the Roman church of the day had moved away from this clear biblical distinctive. The Roman church then and many other religious groups of our day refuse to believe and teach that God’s grace alone is the primary mover in the salvation of sinners. Their refusal is seen in their dependence on human effort to bring about salvation. They rely on things like church tradition; ceremonies and good works to win them divine favour. This is adding to the gospel of God’s grace, which is not the true biblical gospel.
Let James Montgomery Boice, explain “sola gratia.”
“The words sola gratia mean that human beings have no claim upon God. That is, God owes us nothing except just punishment for our many and very wilful sins. Therefore, if He does save sinners, which he does in the case of some but not all, it is only because it pleases him to do it. Indeed, apart from this grace and the regenerating work of the Holy Spirit that flows from it, no one would be saved, since in our lost condition, human beings are not capable of winning, seeking out, or even cooperating with God's grace. By insisting on "grace alone" the Reformers were denying that human methods, techniques, or strategies in themselves could ever bring anyone to faith. It is grace alone expressed through the supernatural work of the Holy Spirit that brings us to Christ, releasing us from our bondage to sin and raising us from death to spiritual life.” [monergism.com]