Ephesians 4:18

Having the understanding darkened. — Of this vanity the first result noted is the intellectual. They are “darkened in the understanding,” and so, “by the ignorance in them alienated from the life of God.” The phrase “the life of God” is unique. It may, however, be interpreted by a similar phrase, the “righteousness of God” (Romans 1:7), i.e., the righteousness given by God. What the life given by God is, we know by our Lord’s own words (John 17:3), “This is the life eternal, to know Thee the only true God, and Jesus Christ whom Thou has sent.” So far as the understanding is concerned, this alienation signifies the loss of the central light of Truth in God, and with it the loss, partial or complete, of the vision of other truths in their right proportion and harmony.

But the second result is moral. St. Paul attributes the alienation from God, or (possibly, though less probably) “the ignorance which is in them,” to the hardness of their heart — for the marginal reading is correct; the word used signifies, almost technically, “callousness” and insensibility. To make his meaning clearer still he adds, “who (or, inasmuch as they) being past feeling, have given themselves over to lasciviousness.” There is precisely a similar current of thought (noting, however, the characteristic difference referred to above) in Romans 1:24, where St. Paul draws out, as consequences of the same vanity, first lusts of uncleanness, next unnatural sin, and at last breaks out into a fearful enumeration of the signs of the reprobate mind. On this side, therefore, “the alienation from the life of God” is the loss of the grace by which He dwells in the soul, and by indwelling gives it the moral and spiritual life.