Romans 4: 1-8:

What then shall we say was gained by Abraham, our forefather according to the flesh? ² For if Abraham was justified by works, he has something to boast about, but not before God. 

If Abraham was justified by works, there would be no need for faith. If we could be forgiven just by doing "good" acts, there would be no need of true repentance as long as you do a good deed after a sin to justify you.

 ³ For what does the Scripture say? “Abraham believed God, and it was counted to him as righteousness.”

Here it says clearly that he believed God, and that belief counted as righteousness. Faith is more powerful than "good" works.

⁴ Now to the one who works, his wages are not counted as a gift but as his due. 

If you work, your paycheck isn't considered a gift, it's considered your due. If you don't work for it, and it's given to you, that's when it's a gift.

 ⁵ And to the one who does not work but believes in him who justifies the ungodly, his faith is counted as righteousness, ⁶ just as David also speaks of the blessing of the one to whom God counts righteousness apart from works:

He who believes will be counted as righteous, because he believed in God.


 

⁷ “Blessed are those whose lawless deeds are forgiven,
    and whose sins are covered;
⁸ blessed is the man against whom the Lord will not count his sin.”

Whoever sin is forgiven, that person is blessed... If you believe and are counted as righteous, you are blessed.