Man used to have a close communion with God, but that communion was destroyed they disobeyed the divine command given by God in the garden of Eden. That sin dragged all humanity with it and from that scenario a wall between God and man was created. Would everything stay like this? Would the failure of a man keep us chained in sin forever? In no way, because Christ descended and dwelt among us and overcame sin and death to give us eternal salvation.
It is good that we understand this that “the Word became flesh.” Let’s read a few verses in the book of John: