Jamieson, Fausset & Brown

In Him was life--essentially and originally, as the previous verses show to be the meaning. Thus He is the Living Word, or, as He is called in Jo1 1:1-2, "the Word of Life." the life . . . the light of men--All that in men which is true light--knowledge, integrity, intelligent, willing subjection to God, love to Him and to their fellow creatures, wisdom, purity, holy joy, rational happiness--all this "light of men" has its fountain in the essential original "life" of "the Word" (Jo1 1:5-7; Psa 36:9).