Our Lord made a covenant with us through baptism in order to give us eternal life. There is in baptism an image both of death and of life, the water being the symbol of death, the Spirit giving the pledge of life. The association of water and the Spirit is explained by the twofold purpose for which baptism was instituted, namely, to destroy the sin in us so that it could never again give birth to death, and to enable us to live by the Spirit and so win the reward of holiness. The water into which the body enters as into a tomb symbolizes death; the Spirit instills into us his life-giving power, awakening our souls from the death of sin to the life that they had in the beginning. This then is what it means to be born again of water and the Spirit: we die in the water, and we come to life again through the Spirit.