Cain's pride and failure to properly interact with (and receive from) his brother, in order to obtain what was pleasing to the Lord, sent him down the road of jealousy, hatred, and murder.
God's problem with Cain wasn't that he farmed fruits and vegetables instead of livestock. God never suggested an occupational change. He was looking for a heart change that exemplified brotherly love, mutual respect, and interdependence.
Cain, the firstborn, had somewhat of a twisted Messiah complex. He was bent on being a "One-Man-Show" in a human family that required interdependence and a healthy reliance upon "every joint of supply" (See Ephesians 4:16).
Jesus, our one true Messiah and Pattern, exemplifies interdependence upon the Father and the Holy Spirit, along with the rest of His human family! We do well to function in like manner.
Refuse any mindset that ever places you outside of God or God outside of you. Stop living as a New Creation Person with an Old Covenant, Adamic mentality. Asking God to "be with us" or attempting to "enter His Presence" is an extreme insult to the finished work of Christ.
His Presence is always a given. His Manifest Presence is enjoyed, through our fixed position in Him, as we receive His Love, bask in His Love, and respond to His Love. All things are of Him, through Him, to Him, and in Him! God was in Christ reconciling the ENTIRE KOSMOS to Himself!
As with all relationships, we must acknowledge, practice and enjoy His Presence in order to grow in our experience of His Presence. His Presence is constant. Our acknowledgment of His Presence is the variable.