Justified/Saved by Faith & Faith Alone

Exactly why we are not justified by our pathetic wavering faith, but by the perfect, unwavering faith of Jesus Christ. All that is required is to believe. At the moment of believing upon Jesus, his faith is imputed to the believer. His testimony becomes the believer’s testimony.

That’s why Paul can say…

20 I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.

I’d have salvation if only I helped that old lady cross the street 25 years ago. Sigh 😔

Sorry my friend, I have to disagree.
It is " I live by faith IN the Son of God" NAB.
Faith is not imputed. It is the hand stretched out to receive.

God called Abraham his friend.

“But you, O Israel, My servant,
Jacob, whom I have chosen,
descendant of Abraham My friend—

Still plenty of old ladies. Get a move on.

Yes this is true.

My point being there is a temporal salvation being addressed by James, Rahab being another example.

Romans 8:35 asks, "Who shall separate us from the love of Christ? Shall trouble or distress or persecution or famine or nakedness or danger or sword?" where the Greek "tis" (Strongs 5101) is translated as "who" here even though the complete meaning includes, "who, which, what, why."
and continues with rhetorical a question of examples that answerable with a "Nope, none of that can separate us from the love of Christ." within the context of a state of being "more than conquerors." Curious state that, being 'more than conquerors' considering we've done none of the conquering ourselves.
I mean, who is able to stop sinning this side of living in an incorruptible body? How can we more than conquer if we can't even at the least conquer them (all of them, do you even realize how many there are to keep track of!!!?)?

And there's that ageless reality that asserts our sin separates us from God (Isaiah 59:2)! Right?
Well, Romans 8:37-39 gives us the key that there is a case where the answer to this is a resounding "NO!"

37No, in all these things we are more than conquerors through Him who loved us. 38For I am convinced that neither death nor life, neither angels nor principalities, neither the present nor the future, nor any powers, 39neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord.

Not even sin can separate God from those in Christ Jesus our Lord!
If that isn't the good news Bonafide Gospel of Jesus, then I don't know what is!

Philippians 3:9 would bolster his argument.

I wouldn't have so many dislikes if I stayed away from the "Calvinist's' threads.

Tough crowd.

No & how you gathered that from what I wrote is a mystery to me.

Paul speaks of righteousness as imputed/credited BUT not faith.
Faith is a human response to the overture of the Holy Spirit as the Gospel is presented.
As I wrote previously, it is the outstretched hand receiving from God.

How can the righteousness that comes from God be divorced from the faith of Christ? If it's not His faith, how is it the righteousness of God? Does your faith produce or provide the righteousness of God?

Christ does not 'believe' for us. Believing is something we do in response to the ministry of the Holy Spirit.
Faith is not the righteousness of God. It is the means of receiving it.
Faith neither produces or provides the righteousness of God.

Wear them as a badge of honor 😎

I guess what I'm asking is this: how is it that a Christian who possesses the Holy Spirit can do nothing apart from Christ, but a non-Christian lacking the Holy Spirit can?

Prevenient (or Enabling) Grace. God comes a frees the will so it can trust in the merits of Christ's death.

The will only or the heart and mind also?
And thank you for taking the time to answer my questions.

Heart & Mind also!

So regeneration precedes the exercise of faith?

I don't know about that. Perhaps the only difference between faith and unbelief is an openness to the possibility of any certain thing, i.e. dunatos (possible) and adunatos (impossible). Therefore, it is impossible to please God without faith.