Genesis 4:3-4

Cain and Abel

³ In the course of time Cain brought to the Lord an offering of _u the fruit of the ground, ⁴ and Abel also brought of _v the firstborn of his flock and of their fat portions. And the Lord _w had regard for Abel and his offering,

1. Cross References
   Leviticus 2:12
   As an offering of firstfruits you may bring them to the Lord, but they shall not be offered on the altar for a pleasing aroma.
   Numbers 18:12
   All the best of the oil and all the best of the wine and of the grain, the firstfruits of what they give to the Lord, I give to you.
   
2. Cross References
   Exodus 13:12
   You shall set apart to the Lord all that first opens the womb. All the firstborn of your animals that are males shall be the Lord 's.
   Numbers 18:17
   But the firstborn of a cow, or the firstborn of a sheep, or the firstborn of a goat, you shall not redeem; they are holy. You shall sprinkle their blood on the altar and shall burn their fat as a food offering, with a pleasing aroma to the Lord.
   Proverbs 3:9
   Honor the Lord with your wealth and with the firstfruits of all your produce.
   
3. Cross References
   Hebrews 11:4
   By faith Abel offered to God a more acceptable sacrifice than Cain, through which he was commended as righteous, God commending him by accepting his gifts. And through his faith, though he died, he still speaks.