Charles Ellicott Commentary Psalms 18:34

"He teacheth my hands to war; So that mine arms do bend a bow of brass." — Psalms 18:34 (ASV)

So that a bow. —Better, and my arms bend a bow of copper. For the copper bow, compare to Job 20:24. Nechushah, χαλκός, is certainly not steel, whether the custom of hardening iron was known to the Jews or not (see Jeremiah 15:12, and the article “Steel,” in Smith’s Biblical Dictionary). The Septuagint and Vulgate have, “you have made my arms a bow of copper.” For this test of strength, we naturally compare the famous bow of Ulysses—

“So the great master drew the mighty bow,
And drew with ease.”— Odyssey, POPE’S translation.