Abraham the Shelim
The Qur'an calls Abraham a Muslim. So does the Torah's official Aramaic translation — and a Christian Hebrew lexicon of 1827 explains the word with the word "Islam."
The command
Genesis 17:1: God appears to Abram and gives two commands — walk before me, and be tamim. Rashi: be whole-hearted, undivided.
The Targum
Targum Onkelos, the official Aramaic Torah recited verse by verse in synagogue since the Talmudic period, renders the verse: "worship before me, and be shelim." The Targum reached for the sh-l-m root — the root of muslim.
The lexicon
Gesenius, Hebrew Lexicon, 1827 — a German Christian Hebraist with no stake in the argument — under the entry shalem: "compare the Arabic, conjugation IV, to devote or submit one's self, particularly to God; hence (Islam) submission to God, religion; (Moslem) one devoted to God, a believer." His words. His proof-texts, in the same entry: 1 Kings 8:61, 11:4, 15:3 — "a heart shalem with the LORD," translated wholehearted. The word already meant total surrender to God inside the Hebrew Bible.
The title
Isaiah 41:8: "seed of Abraham, my friend" — a title God gives no one else. Qur'an 4:125: "God took Abraham as a close friend." The same title, preserved. And 3:67: Abraham was neither a Jew nor a Christian; he was ḥanīfan musliman — upright, submitted.
Sources
Genesis 17:1 (MT; Rashi; Targum Onkelos). Gesenius, Lexicon Manuale Hebraicum (1827), s.v. שלם, p. 612. 1 Kings 8:61; 11:4; 15:3. Isaiah 41:8. Qur'an 3:67; 4:125.