This new life is expressed in the fourth Gospel as a mystical union with Christ which cannot be distinguished in its essence from that of the Pauline epistles; only the way of entrance into it is differently described. Paul makes faith the gate; although the Johannine author does not lay less emphasis on faith than Paul,[329] he does not look at it in quite the same way as the earlier writer, and he speaks of the entrance into the true relation with Christ as a new birth—using the same idea as the pagan mystics. The new birth was described as of the spirit, whereas the first was of the flesh,[330] and the believer’s vital relation to Christ was symbolized by the figures of the vine, of the bread, and of the water of life.[331] Pauline influence may possibly be seen also in the Johannine doctrine of the Holy Spirit—at any rate the fourth Gospel shows that at the time it was written a belief in the Holy Spirit was well established, so that the germ of the doctrine of the Trinity was already planted.[332] The Holy Spirit is variously referred to as the Advocate or Helper, and the Spirit of Truth, which was to be the active agent in edifying believers and rebuking the world when Christ was no longer in the flesh.[333] The purpose of the fourth Gospel then was first to prove that Jesus was the Christ, the Son of God, and secondly to bring men to a belief in this fact which would give them life in Christ.[334] The idea that salvation is present spiritual experience culminates in the Johannine writings; the doctrine that those who hear and believe have already entered into eternal life is clearly stated.[335] Let us now summarize the fundamental ideas of primitive Christianity which we have been examining in this lecture. In the first place, because of his nature and his teachings Jesus was regarded as the revealer of God to men, and at the same time, being the Christ, he was held to be their saviour and redeemer. Paul emphasized Christ’s death and resurrection, John the incarnation as the great central facts. Secondly, love and faith and their effects on man’s relation to God and to his fellow-men were made the essential elements in the Christian life. Thirdly, the doctrine of the mystic union of the believer with the divine Christ and that of the indwelling Holy Spirit were fundamental in both the Pauline and Johannine writings. Revelation, faith, mystic union with the Divine, salvation—our previous studies have shown us that these ideas were both familiar and welcome in the Greco-Roman world of the first century of our era.