Genesis 4

1 And Adam knew Eve his wife; and she conceived, and bare aCain, and said, I have gotten a man from the Lord.

2 And she again bare his brother Abel. And Abel was a akeeper of sheep, but Cain was a tiller of the ground.

3 And in process of time it came to pass, that Cain brought of the fruit of the ground an offering unto the Lord.

4 And Abel, he also brought of the afirstlings of his flock and of the fat thereof. And the Lord had respect unto bAbel and to his coffering:

5 But unto aCain and to his boffering he had not crespect. And Cain was very wroth, and his countenance fell.

6 And the Lord said unto Cain, Why art thou wroth? and why is thy countenance fallen?

7 If thou doest well, shalt thou not be aaccepted? and if thou bdoest not well, csin lieth at the door. And unto thee shall be dhis edesire, and thou shalt rule over him.

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

9 ¶ And the Lord said unto Cain, Where is Abel thy brother? And he said, I know not: Am I my abrother’s bkeeper?

10 And he said, What hast thou done? the voice of thy brother’s ablood crieth unto me from the ground.

11 And now art thou acursed from the bearth, which hath opened her mouth to receive thy brother’s blood from thy hand;

12 When thou tillest the ground, it shall not henceforth yield unto thee her strength; a afugitive and a vagabond shalt thou be in the earth.

13 And Cain said unto the Lord, aMy punishment is greater than I can bear.

14 Behold, thou hast driven me out this day from the face of the earth; and from thy face shall I be hid; and I shall be a fugitive and a vagabond in the earth; and it shall come to pass, that every one that findeth me shall aslay me.

15 And the Lord said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the Lord set a amark upon Cain, lest any finding him should kill him.

* Cain was given a specific talent, and wanted to use his talent to give sacrifices to the Lord. When Cain gave the sacrifice, even though he knew that the Lord wanted the sacrifice a different way, the Lord just told him it was wrong, and understood the circumstances. But Cain, thinking that the manner of the sacrifices was unfair, became jealous and murderous. I don't think the Lord was all that upset with Cain about the sacrifices, it was just that the manner that he was performing the ordinance was wrong. But Cain, upset that he couldn't just worship whichever way he wanted, became so outrageously upset, that he ruined not only his salvation, but he significantly hurt the relationship his children had with the Lord.