Abraham’s faith was accounted to him for righteousness. Man is justified by faith, righteous works, and grace.
Romans 4:20
20 He [Abraham] staggered not at the promise of God through unbelief; but was strong in faith, giving glory to God . . .
Elder Neal A. Maxwell said:
“As one’s will is increasingly submissive to the will of God, he can receive inspiration and revelation so much needed to help meet the trials of life. In the trying and very defining Isaac episode, faithful Abraham ‘staggered not . . . through unbelief’ (Rom. 4:20). Of that episode John Taylor observed that ‘nothing but the spirit of revelation could have given him this confidence, and . . . sustained him under these peculiar circumstances’ [“Discourse,” Deseret News, Mar. 27, 1872, 88]. Will we too trust the Lord amid a perplexing trial for which we have no easy explanation? Do we understand—really comprehend—that Jesus knows and understands when we are stressed and perplexed? The complete consecration which effected the Atonement ensured Jesus’s perfect empathy; He felt our very pains and afflictions before we did and knows how to succor us (see Alma 7:11–12; 2 Ne. 9:21). Since the Most Innocent suffered the most, our own cries of ‘Why?’ cannot match His. But we can utter the same submissive word ‘nevertheless . . .’ (Matt. 26:39).”
(“Swallowed Up in the Will of the Father,” Ensign, Nov. 1995, 23–24.)