Genesis 4:7-9

Darby Translation

⁷ If thou doest well, will not [thy countenance] look up [with confidence]? and if thou doest not well, sin lieth at the door; and unto thee [shall be] his desire, and thou shalt rule over him.

⁸ And Cain spoke to Abel his brother, and it came to pass when they were in the field, that Cain rose up against Abel his brother, and slew him.

⁹ And Jehovah said to Cain, Where is Abel thy brother? And he said, I know not: am I my brother's keeper?