Faith.

Now faith is being sure of what we hope for and certain of what we do not see. This is what the ancients were commended for.

By faith we understand that the universe was formed at God’s command, so that what is seen was not made out of what was visible. By faith Abel offered God a better sacrifice than Cain did. By faith he was commended as a righteous man, when God spoke well of his offerings. And by faith he still speaks, even though he is dead. (Hebrews 11:1-4)