Gd never wanted Yitzchak to be killed: Taanit 4a
Avraham told Eliezer that both he and Isaac would return from the mountain [where he went to slaughter Isaac], and so it occurred, illustrating the Power of Speech: Moed Katan 18a
The Ram from the attempted offering of Isaac was Created on Day 6 of Creation, at Sunset: Pesachim 54a
The Ram's Horn is used in the Rosh HaShanah Service in order to hint at the Offering of Isaac: Rosh HaShanah 16a