Abram was seventy-five years old when he left Haran. He was ninety-nine when God appeared to him, as recorded in this chapter. There had been three divine communications in these twenty-five years--one at Bethel on entering the land, one after the hiving off of Lot, and one after the battle with the Eastern kings. The last-named vision had taken place before Ishmael's birth, and therefore more than thirteen years prior to the date of the lesson. We are apt to think of Abraham's life as being crowded with supernatural revelations. We forget the foreshortening necessary in so brief a sketch of so long a career, which brings distant points close together. Revelations were really but thinly sown in Abram's life. For something over thirteen years he had been left to walk by faith, and, no doubt, had felt the pressure of things seen, silently pushing the unseen out of his life. Especially would this be the case as Ishmael grew up, and his father's heart began to cling to him. The promise was beginning to grow dimmer, as years passed without the birth of the promised heir. As verse 18 of this chapter shows, Abram's thoughts were turning to Ishmael as a possible substitute. His wavering confidence was steadied and quickened by this new revelation. We, too, are often tempted to think that, in the highest matters, 'a bird in the hand is worth two in the bush,' and to wish that God would be content with our Ishmaels, which satisfy us, and would not withdraw us from possessed good, to make us live by hope of good unseen. We need to reflect on this vision when we are thus tempted.