Which Son Did Abraham Take Up the Mountain? A Reflection After the Islamic Celebration of Eid al-Adha

Following the recent observance of Eid al-Adha in the Islamic world, many of us have been reminded of the story of Abraham’s willingness to sacrifice his son in obedience to God. It’s a moment of deep reverence across faiths. But it also brings to light a key difference between the Christian and Islamic understanding of that event.

The Biblical Account vs. Islamic Interpretation

The Bible tells us plainly that it was Isaac. In Genesis 22, the narrative explicitly identifies Isaac by name multiple times as the son whom Abraham was asked to offer. In contrast, the Qur’an retells the story in Surah As-Saffat 37:99–113 but does not name the son.¹ It describes the vision, the son’s willingness, and God’s intervention, yet leaves his identity ambiguous.

Early Islamic commentators offered differing views. Some identifying the son as Isaac, others as Ishmael. Over time, the majority Islamic view came to regard Ishmael as the intended sacrifice.² This understanding is reflected in the works of influential scholars like Ibn Kathir and al-Tabari³, and is now the dominant interpretation across the Muslim world. Modern scholars such as Reuven Firestone have documented how this interpretive shift became firmly rooted in Islamic theology by the 9th century.

Historical and Textual Evidence

This contrasts with the Torah, which contains the account of Isaac’s near-sacrifice and was written over a thousand years before the Qur’an. Manuscript evidence, such as the Dead Sea Scrolls, confirms the Torah’s textual consistency centuries before Christ.⁴

While the Qur’an retells much of the biblical story, it also claims scriptures like the Torah and the Gospels were altered or corrupted, a belief known in Islamic tradition as tahrif.⁵ However, the Qur’an offers no historical or manuscript evidence to support this claim.

The Theological Significance of Isaac

For Christians, the identity of the son is crucial not just historically but theologically. The Book of Genesis is clear: Isaac is the child of promise, born to Sarah who was barren and well past childbearing age as a result of God’s supernatural intervention. Hagar, the mother of Ishmael, was Sarah’s Egyptian servant.

Paul later writes about this distinction in Galatians 4:22–31, explaining that the two women represent two covenants. Hagar represents slavery and human striving. Sarah represents the promise of God and the freedom found in His covenant. The difference between the children is not just about ancestry. It’s about the nature of salvation itself.

The Nature of Abraham’s Test

This detail also changes the meaning of Abraham’s test. If the son on the altar had been Ishmael, the child born through Abraham’s attempt to bring about God’s promise by human effort, the test would have been difficult but not extraordinary. Isaac, on the other hand, was the miraculous son, born to a barren woman through God’s direct intervention.

To offer up Isaac was to surrender not only a beloved son but the very promise God had given. Abraham’s obedience was not merely a willingness to let go of something precious. It was the surrender of the promise itself, the promise to make his offspring as numerous as the stars, now bound to the altar. Abraham faced the apparent death of the future God had assured him, and still, he believed God would raise what He had asked to be laid down.

A Foreshadowing of Christ

Isaac’s near-sacrifice is one of the clearest foreshadowings (Messianic Prophecy) of Christ in all of Scripture. A beloved son is offered up by his father, carrying the wood for the offering, but in the end, God provides the substitute. This picture prepares us for the cross, where God’s own Son was not spared but given up for our redemption.

Islam’s Theological Reframing

Islam reframes the story by placing Ishmael on the mountain. This shift is essential to Islam’s theological structure. It links the story of Abraham directly to Ishmael’s descendants and to Muhammad himself. In doing so, it roots Islam’s prophetic claim in Ishmael’s lineage. But in light of Scripture, this lineage is not the one through whom the covenant of promise was given.

According to the Bible, it’s not Ishmael but Isaac who carries the blessing. Paul’s words in Galatians are pointed: those who come through Hagar represent the covenant of bondage, while the promise belongs to the free woman. In this light, Muhammad doesn’t descend from the line of God’s promise, but from the line of human striving, of attempting to secure God’s blessing outside of His appointed means.

The Fundamental Difference

The Islamic account does more than change a name, it fundamentally redefines the spiritual inheritance. By reassigning the child on the altar from Isaac, the child of promise, to Ishmael, the product of human striving, it severs the story of redemption from God’s covenant blessing. By choosing Ishmael, Islam aligns itself with a covenant defined by bondage and human effort rather than freedom and divine promise, emphasising salvation and blessing through the works of our own hands, rather than trusting in God’s sovereign and gracious promise.

Conclusion: Historical Confidence and Spiritual Conviction

For Christians, this discussion is not merely a debate for its own sake. It’s about recognising the truth of God’s plan through history. The story of Abraham and Isaac affirms the nature of God’s covenant, one based on promise and fulfilled in Christ. It reminds us that God’s salvation was never about lineage or human effort but about faith in His Word and His provision.

So when we consider the question, which son did Abraham take up the mountain, we answer not only with historical confidence but with deep spiritual conviction. It was Isaac. And that moment was not just a test of faith, it was a glimpse of the Gospel to come.