Abraham did not view it as killing Isacc, he viewed it thorugh the promise was to come through Isacc and that city that's builder is God.
Hebrews 11:8-10, 17-19 “By faith Abraham obeyed when he was called to go out to a place that he was to receive as an inheritance. And he went out, not knowing where he was going.9 By faith he went to live in the land of promise, as in a foreign land, living in tents with Isaac and Jacob, heirs with him of the same promise.10 For he was looking forward to the city that has foundations, whose designer and builder is God......17 By faith Abraham, when he was tested, offered up Isaac, and he who had received the promises was in the act of offering up his only son,18 of whom it was said, “Through Isaac shall your offspring be named.”19 He considered that God was able even to raise him from the dead, from which, figuratively speaking, he did receive him back.”
Abraham believe God and how He promised to keep the covenant in Genesis 15:7-21
“And he said to him, “I am the Lord who brought you out from Ur of the Chaldeans to give you this land to possess.”8But he said, “O Lord God, how am I to know that I shall possess it?”9 He said to him, “Bring me a heifer three years old, a female goat three years old, a ram three years old, a turtledove, and a young pigeon.”10 And he brought him all these, cut them in half, and laid each half over against the other. But he did not cut the birds in half.11 And when birds of prey came down on the carcasses, Abram drove them away.
12 As the sun was going down, a deep sleep fell on Abram. And behold, dreadful and great darkness fell upon him.13Then the Lord said to Abram, “Know for certain that your offspring will be sojourners in a land that is not theirs and will be servants there, and they will be afflicted for four hundred years.14 But I will bring judgment on the nation that they serve, and afterward they shall come out with great possessions.15 As for you, you shall go to your fathers in peace; you shall be buried in a good old age.16 And they shall come back here in the fourth generation, for the iniquity of the Amorites is not yet complete.”
17 When the sun had gone down and it was dark, behold, a smoking fire pot and a flaming torch passed between these pieces.18 On that day the Lord made a covenant with Abram, saying, “To your offspring I give this land, from the river of Egypt to the great river, the river Euphrates,19 the land of the Kenites, the Kenizzites, the Kadmonites,20 the Hittites, the Perizzites, the Rephaim,21 the Amorites, the Canaanites, the Girgashites and the Jebusites.”
