Heb 11:4 By faith Abel offered to God a more excellent sacrifice than Cain, through which he obtained witness that he was righteous, God testifying of his gifts; and through it he being dead still speaks
Hebrews 11 is a Faith chapter. It lays out the “hall of faithers” if you will. Faith as outlined by F.B. Meyer in his devotional as “…the sixth sense. It makes us as sure of unseen or future things, which we know about only through the divine Word”
Abel is the first martyr for the faith, he lived by it and died for it. He still speaks in the Scriptures though dead. That is, his faith is still spoken of though he has been dead thousands of years. He is the first to teach us that a man is justified by faith alone apart from works. It’s not the sacrifice that he is commended for, but his obedient in faith. This is the testimony he left to all succeeding generations of how to receive righteousness. In this God did not suffer Abel’s faith to die with him, but would raise others to obtain like precious faith; and so he did in a little time.