And never your own payment, works, worthiness, nor effort.
Yes, by grace alone; how Catholic! I would like to point out a serious misunderstanding among Protestants about what Catholic believe is the relationship between faith and works. Catholics do not believe that we must add the merits of our own works to the saving work of Jesus Christ. How does a Catholic believe that he is saved? By asking for it. Salvation first comes through Baptism; no good works are required. After Baptism, if a person falls back into serious sin, then he restored to grace by repentance and and confession; he just asks for it! No good works are required. (For now let us hold off on the question of the nature and necessity of baptism and confession. This is a different question. The question at hand is the relationship between grace and works.) The good works that Catholics say are necessary for salvation are what is produced after being justified, the product of what you would call "saving faith," if I understand you correctly.
All saving faith results in a new birth, and the new life of Christ within. It is the expression of His life that produces fruit. It is the Spirit that testifies to the soul of every true believer, that he belongs to Him.
And this we Catholics call Sanctifying Grace.
For, as you know, there are many who claim faith in Jesus Christ who continue to live in the sins that Paul warns that will exclude us from the kingdom of God.
Ah, here I take it that you mean Roman Catholics, but of course it equally applies to Orthodox and all others.
You are not saying that there are not also Protestants who claim faith in Jesus Christ and who continue in lives of sin, are you?
We also know that not all who call on the name of Christ are His.
The wheat grows with the tares. God separates them at harvest-time.
So there can be no assurance that what the faith we proclaim is actually saving faith?