This is a good sequence of learning, except for the last one. “Salvation” is not a belief, but an experience. It is the “infinite idea forever developing itself,” as you referenced Mary Baker Eddy. And it is evidenced by our works, not our words.
There is a danger of thinking that one has “arrived” when he hasn’t. That is why we need to humbly thank God for the works and not think that we have done anything of ourselves. It looks like you got caught up in an intellectual squabble, which can only lead to confusion worse confounded. We gain salvation by faith in God’s grace. And we evidence that salvation by our works, not our words. And what is it that we need to be “saved” from? The false beliefs that sin, disease, and death are real, and have power derived either from God or in spite of God.
Mrs. Eddy explains this very clearly. On page 51 of S&H, she writes, regarding Jesus, “his consummate example was for the salvation of us all, but only through doing the works which he did and taught others to do. His purpose in healing was not alone to restore health, but to demonstrate his divine Principle.” This divine Principle is the grace of God. It is what ‘saves” us from the belief that we are anything other than the image and likeness of God. But we have a responsibility to take this divine Principle and write it on our foreheads, obey its commands (the ‘still, small voice’), thus proving by our works that we are growing (obtaining salvation).
When we experience the healing of sin, disease, or death, our salvation rests in recognizing that it is the power of Truth (the grace of God) in action, not the result of any human ability on our part, or that of anyone else.