2 Kings 7:19
And that lord answered the man of God, and said, Now, behold, if the LORD should make windows in heaven, might such a thing be? And he said, Behold, thou shalt see it with thine eyes, but shalt not eat thereof. And that lord answered the man of God, and said, Now, behold, if the LORD should make windows in heaven, might such a thing be? And he said, Behold, thou shalt see it with thine eyes, but shalt not eat thereof.
Elisha's answer was spoken to the officer who doubted his prophecy of plenty for besieged Samaria, questioning how God could provide what seemed impossible. The officer was told he would see the promised abundance with his own eyes but would not eat of it or share in it. The promise was fulfilled when the Syrians fled and Samaria received their abandoned food. The officer died, trampled at the gate as the people rushed out to obtain provisions, so his unbelief cost him a share in the promised blessing.
His experience warns that delay in obeying God's instruction for lack of apparent means leads to witnessing the promised work succeed while missing its blessings. To doubt because the means are not seen is to repeat the lord's disbelief in Elisha's promise of food, which left him seeing its fulfillment but not sharing in it. It likewise warns those who doubt Christ's coming in this generation that they will see the promised event but have no part in its blessing.