Lutheran vs. Catholic -- What's the difference?

One of the big lies that is so prevalent in America today is that all religions are the same.  Even Christians say that.  It is a lie.  They are not all the same.  

In the link here, https://www.facebook.com/DailyWire/videos/288785111777404/ ,  Charlie Kirk (a conservative commentator and a Jew) asks a Roman Catholic priest about salvation.  The priest gives an answer that is perfectly consistent with Roman Catholic theology.  It is appalling.

The most appalling claim is that you don't need Jesus to be saved.  You can renounce Jesus and even the very existence of God and can still be saved.  Really.  He says that, and backs it up with Vatican II proclamations.

Secondly, he says that the grace of Christ is not enough.  You need to follow up with that and cooperate with Christ to attain your salvation.  He says that Luther should have said "By grace first" rather than "By grace alone."  So, he highlights that Lutherans and Roman Catholics are still far, far apart on the matter of how one is saved and where one finds confidence in salvation.

If I need to add something to the grace of Christ, I am going to hell for sure.  The very problem from the start is that I am corrupt and cannot fulfill the Commandments of God.  Even now, as a Christian who desires to be godly and obedient, even now I cannot fulfill the Commandments of God.  The only thing I can add to the grace of Christ is my corrupt failures.  THAT is supposed to help save me?!?  That's the very reason I need to be saved!!!

According to the priest in the interview, atheists can be saved.  A vehement rejection of God and his word is, apparently, not enough to condemn anyone.  However, this is what the Roman Catholic Church says about Lutherans:  "If any one saith, that justifying faith is nothing else but confidence in the divine mercy which remits sins for Christ's sake; or, that this confidence alone is that whereby we are justified; let him be anathema." (Session IV, Canon XII)  NOTE: This has never been repudiated.  So, according to Roman Catholic theology, an atheist can be saved, but a confessional Lutheran is damned for sure.

So, the difference is massive.  It is tragic, but it dare not be ignored or glossed over.  Salvation and comfort for sinners is at stake.

Lutherans uphold what the Scriptures declare about salvation so that all may have the comfort and confidence of knowing God's favor rests upon you.  Scripture references abound, but I will highlight two.

Romans 3:20-28
For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin.  
But now the righteousness of God has been manifested apart from the law, although the Law and the Prophets bear witness to it—the righteousness of God through faith in Jesus Christ for all who believe. For there is no distinction: for all have sinned and fall short of the glory of God, and are justified by his grace as a gift, through the redemption that is in Christ Jesus, whom God put forward as a propitiation by his blood, to be received by faith. This was to show God's righteousness, because in his divine forbearance he had passed over former sins. It was to show his righteousness at the present time, so that he might be just and the justifier of the one who has faith in Jesus.
Then what becomes of our boasting? It is excluded. By what kind of law? By a law of works? No, but by the law of faith. For we hold that one is justified by faith apart from works of the law.

Ephesians 2:8-9
For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.

Salvation is by grace alone -- God's gift, won by Jesus Christ, and given to sinners.  Salvation is by faith alone -- the works were done by Jesus Christ and are credited to sinners.  Ephesians even highlights that saving faith is given by God.  We have nothing in ourselves to boast about.  It is all God's doing for us.  And, since God did it, we can be certain that everything has been done completely and perfectly.