We can never fully grasp the immensity of the cataclysmic events that unfolded in Genesis 3. We begin the chapter with a harmonious earth beautifully ordered, with man and woman taking their place obediently in their realm before God. We end the chapter with sin on the march, all creation under judgement, everything bearing the marks of the curse and man barred from the garden of Eden.
In the midst of all this chaos we find there is gospel hope. There is hope of a better day. It first comes with the promise in v15 and is found in these words of the Lord God to the snake (Satan).
And I will put enmity
between you and the woman,
and between your offspring and hers;
he will crush your head,
and you will strike his heel.’
The seed of the woman, Jesus Christ, will have His heel struck and so will be brought to the cross. But in that cross He will crush the head of Satan and render him powerless.
This is the only bright word amidst the devastation, ensuing from the fall, that was all around him. And yet in v20 we read Adam named his wife Eve, because she would become the mother of all the living. Logic would determine that he must call her the mother of all the dying, because that is what prevailed all around. There was no life in sight. And yet, hanging on to the promise of v15, he, in faith, declared her to be Eve. He asserted that God would bring life through the crushing of Satan. Thereby he named her to be the mother of the living. This is amazing faith.
In v21 we see two further critical ingredients of the message of the gospel. In v7b we read how, consequent to the fall, Adam and Eve realised that they were naked; so they sewed fig leaves together and made coverings for themselves. However, this was to no avail in being a proper cover. In v21 we read how God made garments for them. Before the fall there was no need of any garments because everything was pure and there was no shame. The fall brought shame and Adam and Eve knew they needed to be covered up. The need for coverings, whether they be fig leaves or skins, testify to the fact of mankind in sin. The wearing of garments by ourselves is a continued reminder that we are sinners. The coverings are an ongoing testimony to the reality of sin and us being sinners.
We also learn in v21 that the giving up of the life of another is necessary for a suitable covering to be made so that we can be acceptable with God. The coverings of v7 prove to be useless because they were man-made. But then the God-made (and provided) coverings of v21 were entirely sufficient. In the providing of these garments we see a foreshadowing of the ultimate giving up of life and shedding of blood to provide a covering for others when our Lord Jesus died on the cross. There he provided a coat of righteousness to all who believe.
So there is the gospel. The promise, faith, sin and the substitutionary offering. All this reminds us of our need of Christ and the provision of salvation in Christ.