The command is unambiguous. In Targum Pseudo-Jonathan on Genesis 24:3, Abraham makes Eliezer swear by the Word of the Lord God, whose habitation is in heaven on high, the God whose dominion is over the earth — that no Canaanite woman will enter the covenant line.
The Aramaic phrase Memra di-Yeya — the Word of the Lord — is the Targum of Pseudo-Jonathan's signature formula for the active divine presence. The oath is sworn not on an abstract deity but on God's engaged and near Word.
Why no Canaanites? The rabbis offered several answers over the centuries. The Midrash (Bereshit Rabbah 59:8, c. 300–500 CE) saw it as a cultural and moral concern: the Canaanite cities around Hebron had ethical practices Abraham could not accept for his son. Others saw it as preserving the spiritual line that had begun in Haran, carried through Sarah, and must now find its next chain-link in Rebecca.
The two-part description of God in this verse is striking. Whose habitation is in heaven on high — He is transcendent. Whose dominion is over the earth — He is immanent. The Targum places both claims in the same breath so the oath carries cosmic weight.
The Maggidim read this as Abraham's final strategic decision. The takeaway: the generation after you inherits the habits you wed. Choose carefully whose daughter or son joins your household — the covenant line may depend on who walks in the door.