The deep sleep (tardemah) is the same word used for Adam's sleep in Genesis 2:21 — a sleep God sends, not a natural sleep. The 'horror of great darkness' signals that what follows is a prophetic vision of significant weight. God is about to reveal a future that includes suffering — the Egyptian captivity — before the fulfilment.
Memory phrase: God prepares us before He shows us hard truths.
Talk about it: Abram felt darkness and dread before God spoke. Have you ever felt scared or heavy before something important? What happened?
Prayer: God, when hard or heavy things come, help me trust that You are still with me — and that You are preparing me for something good.