Giants. — Heb., Nephilim, mentioned again in Numbers 13:33, and apparently a race of great physical strength and stature. Nothing is more probable than that, at a time when men lived for centuries, human vigour should also show itself in producing not merely individuals, but a race of more than ordinary height. They were apparently of the Cainite stock, and the text carefully distinguishes them from the offspring of the mixed marriages. The usual derivation of the name is from a root signifying to fall; but Lenormant (Origines de l’Histoire, p. 344) prefers pâlâ, which means “to be wonderful,” and compares the Assyrian naptû, “unique in size,” often found in the cuneiform inscriptions as the denomination of an ogre.
The same became mighty men. — Heb., They were the mighty men that were of old, men of name. “Gibborim,” mighty men (see Genesis 10:8), has nothing to do with stature, but means heroes, warriors. It is also generally used in a good sense. The children of these mixed marriages were a race of brave fighting men, who by their martial deeds won for themselves reputation.