In the Garden of Eden after the first sin, the initial evidence came when Adam and Eve saw “that they were naked.” They had been naked all along, but not until sin came did they take their eyes off God and put them on themselves. This is always what sin does. Before, God had been the center of their attention and devotion. Sin entered the picture, and their focus became centered squarely on themselves.
God in His grace intervened because all the ways we try to use to cover our sin never work. God took an innocent little animal, killed it, and covered Adam and Eve with its skin. That animal became the first to the know the expensive toll that sin takes on one’s life.
Hebrews 9:22, “In fact, the law requires that nearly everything be cleansed with blood,and without the shedding of blood there is no forgiveness.”