Which son did Abraham offer in sacrifice?

Genesis 22

¹After these things, God tested Abraham, and said to him, “Abraham!” He said, “Here I am.” ²He said, “Now take your son, your only son, Isaac, whom you love, and go into the land of Moriah. Offer him there as a burnt offering on one of the mountains which I will tell you of.” ³Abraham rose early in the morning, and saddled his donkey; and took two of his young men with him, and Isaac his son. He split the wood for the burnt offering, and rose up, and went to the place of which God had told him. ⁴On the third day Abraham lifted up his eyes, and saw the place far off. ⁵Abraham said to his young men, “Stay here with the donkey. The boy and I will go over there. We will worship, and come back to you.” ⁶Abraham took the wood of the burnt offering and laid it on Isaac his son. He took in his hand the fire and the knife. They both went together. ⁷Isaac spoke to Abraham his father, and said, “My father?” He said, “Here I am, my son.” He said, “Here is the fire and the wood, but where is the lamb for a burnt offering?” ⁸Abraham said, “God will provide himself the lamb for a burnt offering, my son.” So they both went together. ⁹They came to the place which God had told him of. Abraham built the altar there, and laid the wood in order, bound Isaac his son, and laid him on the altar, on the wood. ¹⁰Abraham stretched out his hand, and took the knife to kill his son. ¹¹Yahweh’s angel called to him out of the sky, and said, “Abraham, Abraham!” He said, “Here I am.” ¹²He said, “Don’t lay your hand on the boy or do anything to him. For now I know that you fear God, since you have not withheld your son, your only son, from me.” ¹³Abraham lifted up his eyes, and looked, and saw that behind him was a ram caught in the thicket by his horns. Abraham went and took the ram, and offered him up for a burnt offering instead of his son. ¹⁴Abraham called the name of that place “Yahweh Will Provide”. As it is said to this day, “On Yahweh’s mountain, it will be provided.” ¹⁵Yahweh’s angel called to Abraham a second time out of the sky, ¹⁶and said, “‘I have sworn by myself,’ says Yahweh, ‘because you have done this thing, and have not withheld your son, your only son, ¹⁷that I will bless you greatly, and I will multiply your offspring greatly like the stars of the heavens, and like the sand which is on the seashore. Your offspring will possess the gate of his enemies. ¹⁸All the nations of the earth will be blessed by your offspring, because you have obeyed my voice.’” ¹⁹So Abraham returned to his young men, and they rose up and went together to Beersheba. Abraham lived at Beersheba.

Genesis 22:1-19 (WEB) · context

The Quran

¹⁰⁰My Lord! Vouchsafe me of the righteous. ¹⁰¹So We gave him tidings of a gentle son. ¹⁰²And when (his son) was old enough to walk with him, (Abraham) said: O my dear son, I have seen in a dream that I must sacrifice thee. So look, what thinkest thou? He said: O my father! Do that which thou art commanded. Allah willing, thou shalt find me of the steadfast. ¹⁰³Then, when they had both surrendered (to Allah), and he had flung him down upon his face, ¹⁰⁴We called unto him: O Abraham! ¹⁰⁵Thou hast already fulfilled the vision. Lo! thus do We reward the good. ¹⁰⁶Lo! that verily was a clear test. ¹⁰⁷Then We ransomed him with a tremendous victim. ¹⁰⁸And We left for him among the later folk (the salutation): ¹⁰⁹Peace be unto Abraham! ¹¹⁰Thus do We reward the good. ¹¹¹Lo! he is one of Our believing slaves. ¹¹²And we gave him tidings of the birth of Isaac, a prophet of the righteous. ¹¹³And We blessed him and Isaac. And of their seed are some who do good, and some who plainly wrong themselves.

Quran 37:100-113 (Pickthall) · context

What early Muslim scholars said