“Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear.”
Hebrews 11:3

Isn’t it amazing that after telling us the worlds were framed by the word, he doesn’t tell us how God spoke and framed the world but rather how men used their faith and framed their world? He begins with Abel:
“By faith Abel offered unto God a more excellent sacrifice than Cain, by which he obtained witness that he was righteous, God testifying of his gifts: and by it he being dead yet speaketh.” Hebrews 11:4
Abel offered a God he couldn’t see an excellent sacrifice- it takes some faith to do that! If you can’t see who you’re giving to, why not just give anything anyhow? Like Cain, who gave in the process of time (delayed) in contrast with Abel who gave the first of his flocks: Genesis 4:3-4
And because Abel acted in faith, and the Bible already told us:
“…for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.” Hebrews 11:6
He obtained witness that he was righteous! He received a great testimony from God because he offered an excellent sacrifice in faith. How do you offer to God? Anything, anyhow at anytime you like?

Bible Reading Plan: Exodus 6, Luke 12