“Behold the Lamb of God, which taketh away the sin of the world”.
The words “taketh away” are written here in the present tense. It is a work that goes on; for also believers daily offend in many things (James 3:2). Christ continuously takes away sin. Not by suffering for it time and again. “For in that He died, He died unto sin once; but in that He liveth, He liveth unto God” (Rom. 6:10). But Christ continuously shows His sacrifice, and then asks the Father for reconciliation, forgiveness and adoption on behalf of His own people.
“Behold the Lamb of God” – not with the eye of the body. A great many people have seen Christ with this eye when He was on earth, without understanding that He takes away the sin of the world.
Did you ever behold Christ in such a way that you saw that He takes away the sin of the world, and so your sin also (for you too belong to the world)? That is faith. When a man has faith, he sees this. By this you can examine yourself, whether you have true faith. We may talk about seeing the Lamb of God, but usually this is not the right seeing. The right seeing is, that we cannot go without it. When through true faith a man sees the Lamb of God, then he embraces It. However, sometimes man sees these things from afar, before Christ has been revealed unto him, namely the possibility on God’s side to be saved. This serves for his support, although this is not a soul-saving view. Therefore, man must never rely thereon, and never think that this is something that could influence salvation either way, for salvation only exists through the faith of appropriation. “He that believeth and is baptized shall be saved; but he that believeth not shall be damned” (Mark 16:16).
(From: Meditations, 30 January. Sermon on John 1:29, 9 February 1928 in Rotterdam.)