Romans 4:3-6

4:3 For what does the scripture say? “Abraham believed God, and it was credited to him as righteousness.” 4:4 Now to the one who works, his pay is not credited due to grace but due to obligation. 4:5 But to the one who does not work, but believes in the one who declares the ungodly righteous, his faith is credited as righteousness.

4:6 So even David himself speaks regarding the blessedness of the man to whom God credits righteousness apart from works:

Romans 4:9

4:9 Is this blessedness then for the circumcision or also for the uncircumcision? For we say, “faith was credited to Abraham as righteousness.”

Romans 4:20-25

4:20 He did not waver in unbelief about the promise of God but was strengthened in faith, giving glory to God. 4:21 He was fully convinced that what God promised he was also able to do. 4:22 So indeed it was credited to Abraham as righteousness.

4:23 But the statement it was credited to him was not written only for Abraham’s sake, 4:24 but also for our sake, to whom it will be credited, those who believe in the one who raised Jesus our Lord from the dead. 4:25 He was given over because of our transgressions and was raised for the sake of our justification.