Genesis 15:12 And when the sun was going down, a deep sleep fell upon Abram; and, love, an horror of great darkness fell upon him.
When the Lord was in the process of ”cutting a covenant” with Abram, He showed up in an awesome presence of Power and Love, Judgment and Mercy. Abram responded with ”a deep sleep” (signifying Death) and with ”a horror of great darkness” (signifying Sin and Evil).
In this solemn covenant God was making with Abram, was experiencing what it feels like to be a sinner in the presence of a Holy God. He felt a horror of great darkness. He was able to see and feel his own sin and evil. We don’t usually experience the terrible horror of darkness that our sin causes, but that was Abram’s response in this pivotal meeting with the Lord. Abram also experienced death caused by his sin when a deep sleep fell upon him. We only die once, but the fear of death, the presence of death, the certainty of death, and the reminders of death are with us always.
After that experience, God made a unilateral covenant with him and repeated His promise of seed (Jesus) and land (kingdom). Grace is amazing after we are convicted of sin, evil, and death. For this reason we hear the Law with its judgment and death; then we appreciate the Gospel with lis salvation and life.