What was wrong with Caine's sacrifices?

It was Cain's attitude that was at fault.

Cain became a cultivator of the ground and, “at the expiration of some time,” he, as well as his younger brother Abel, brought offerings to present to God, feeling the need to gain God’s favor.

Cain’s offering of “some fruits of the ground,” however, was not ‘looked upon with any favor’ by God. (Ge 4:2-5; compare Nu 16:15; Am 5:22.)

While some point out that Cain’s offering is not said to be of the choicest fruits whereas Abel’s offering is specified to have been of the “firstlings of his flock, even their fatty pieces,” the problem was not in the quality of produce that Cain offered.

As Hebrews 11:4 points out, Cain’s offering lacked the motivation of faith that made Abel’s sacrifice acceptable. The fact that God did not view Cain’s offering with favor may also have been because his offering was bloodless, whereas Abel’s represented a life poured out.

God knew what was in Cain's heart. He had a wrong attitude as was borne out by the fact that he later killed his brother out of jealousy.

He offered the fruit of the ground, not the best fruit. God rejected Cain's offering, but not Cain and gave him a warning instead. Cain reacted by getting mad. The commandment for shedding of the sacrificial animals blood was a type of the sacrifice that would be made for sin.

It is symbolism. The Bible talks a lot about sacrifice of animals and then the ultimate sacrifice is Jesus. Since the crucifixion of Jesus -- sacrificing, burnt offerings, and so on is no longer required. In the Old Testament a particular animal -- a lamb -- was typically sacrificed. Jesus is called the Lamb of God.

Cain and Abel are also a representation of the flesh and the spirit.... God said the payment for sin was "blood".... Abel presented the "blood" sacrifice... Cain presented the "work of his own hands", the "work of the flesh", and it did NOT satisfy God's demand for the "blood" sacrifice..... Cain was "religious"... he was manufacturing his OWN righteousness and not submitting to GOD'S

He was a very jealous and rebellious person. Cains sacrifice was rejected because it was offered at Satan's command, not the Lords; it was not offered in faith. He fought God, worshipped Lucifer and slew Abel.

Cain did not " obey"................

read and study and then read some more.............................

God requires obedience..............there is NO exception.......not even to " Christians" who rely on .... forgiveness.

Obedience IS required.

There is NO such thing as " Feminine nature" coming into the play. STOP teasing God's word(s).

That only adds to the problem.

I don't mean to sound "preachy" but the verse says "And the Lord had regard for Abel and his offering, but for Cain and his offering he had no regard" (Gen. 4:4)

God didn't care for Cain, plain and simple. IMHO

No, Caine didn't sacrifice his best fruits, he kept them for himself. That's what was wrong with his sacrifice.

Your god sure is demanding, isn't he? :p