Because it is before men that our faith is witnessed and proven.
It is not proven before God because God already knows if we are among the elect or not. Actually, He knew from eternity past if our faith would be true or dead.
It is before men that we prove our claims to faith. It is there that is the arena.
“Demonstrate your faith to me…”"I will demonstrate my faith to you…"Not to God…but to man…
This is incomplete and therefore incorrect.
First Justification – Going to a Foreign Land
1 The LORD had said to Abram, “Leave your country, your people and your father’s household and go to the land I will show you. 2 I will make you into a great nation and I will bless you; I will make your name great, and you will be a blessing. 3 I will bless those who bless you, and whoever curses you I will curse; and all peoples on earth will be blessed through you.” 4 So Abram left, as the LORD had told him; and Lot went with him. (Genesis 12:1-4)
By faith Abraham, when called to go to a place he would later receive as his inheritance, obeyed and went, even though he did not know where he was going. By faith he made his home in the promised land like a stranger in a foreign country; he lived in tents, as did Isaac and Jacob, who were heirs with him of the same promise. (Hebrews 11:8-9)
Hebrews makes it clear that Abraham was justified in Genesis 12 since it is specifically commending the true faith of all the OT “heroes” listed. Given the fact that Abraham’s departure from his homeland would have been a “public” event, I’ll grant that this was “before men”.
However, this seems to create a problem for the evangelical position because Abraham was justified by demonstrating his faith before men back in Genesis 12 - a decade before he was also justified by faith in Genesis 15:6.
Second Justification – Believing God
5 He took him outside and said, “Look up at the heavens and count the stars—if indeed you can count them.” Then he said to him, “So shall your offspring be.” 6 Abram believed the LORD, and he credited it to him as righteousness. (Genesis 15:5-6)
What then shall we say that Abraham, our forefather, discovered in this matter? If, in fact, Abraham was justified by works, he had something to boast about—but not before God. What does the Scripture say? “Abraham believed God, and it was credited to him as righteousness.” (Romans 4:1-3)
6 Consider Abraham: “He believed God, and it was credited to him as righteousness.” (Galatians 3:6)
You see that his faith and his actions were working together, and his faith was made complete by what he did. And the scripture was fulfilled that says, “Abraham believed God, and it was credited to him as righteousness,” and he was called God’s friend. You see that a person is justified by what he does and not by faith alone. (James 2:22-24)
Both Paul and James clearly declare that Abraham was justified when he believed God. No men were present to witness the event when Abraham counted the stars - the event was a private moment between Abraham and God.
Third Justification – Sacrificing Isaac
12 “Do not lay a hand on the boy,” he said. “Do not do anything to him. Now I know that you fear God, because you have not withheld from me your son, your only son.” (Genesis 22:12)
20 You foolish man, do you want evidence that faith without deeds is useless? 21 Was not our ancestor Abraham considered righteous for what he did when he offered his son Isaac on the altar? 22 You see that his faith and his actions were working together, and his faith was made complete by what he did. (James 2:20-22)
Abraham was justified (considered righteous) a third time in the sacrifice of Isaac. Again, no men were present to witness the event (unless you want to count Isaac) - the event was a private moment between Abraham and God.
These three moments in the life of Abraham indicate that justification is not a once-for-all event, but a process that occurs throughout the life of the believer.
Finally, you have written, “It is not proven before God because God
already knows if we are among the elect or not.” However, in the passage from Genesis 22, the angel, speaking for God, says the following: “Now I know that you fear God, because you have not withheld from me your son, your only son.” “Now I know” implies a temporal aspect to God’s work in the life of Abraham. Yes, God is omniscient, but he continues to work within the temporal framework that He Himself established.