On the first Sunday after Pentecost the Church celebrates the Solemnity of the Most Holy Trinity. This revealed doctrine of God's nature is that the eternal God is one in essence and being, yet three distinct persons—God the Father, God the Son (the Incarnate Jesus Christ), and God the Holy Spirit. This is the central and greatest mystery of the Christian faith. An everlasting and loving union with the Holy Trinity is the final end for which mankind is created. The divine inner life of the Holy Trinity is generously given to us as sanctifying grace through the Church's Sacraments, which is fully and perfectly possessed by the saints in heaven.