He may have the joy of making others share the same divine love and joy, and therefore adds, "As thou hast given him power over all flesh, that he should give eternal life to as many as thou hast given him. And this is life eternal, that they might know thee, the only true God, and Jesus Christ, whom thou hast sent." But while He as the Son was to be the first revealer of God the Father, He was not, therefore, to be the only revealer. He was the firstborn of many brethren in whom the same love was to be reproduced, and by whom the same high duty was to be performed. If the light of the glory of God shone directly in the face of Jesus Christ, that light was to be transmitted to those who were to shine as lights in the world, that others seeing them might glorify the same God. For now, as ever, God in a real sense manifests Himself in the flesh. Hence our Lord's desire that His brethren should, as sons, reveal the Father, like Himself the Son. He says accordingly, "As thou hast sent me into the world, even so have I also sent them into the world." Sent whom? Not apostles only, but those also who should believe through their word; not ministers of the Church only, but members also; all, in short, who were qualified to convince the world that God was a Father, by convincing it of this truth, that God had sent His Son to save sinners--the "faithful saying, worthy of all acceptation." But the question is further suggested, What is this qualification? What is this which men must possess in order to accomplish Christ's purpose of inducing the world to believe? What is this evidence of Christianity which they are to present to the eyes of unbelieving men, by seeing which these are to know and glorify God as their Father in Christ? We reply, it is the oneness of those who are to be ambassadors from God and fellow-workers with Christ. "I pray for them," He says, and not for them only, but "for them also who shall believe on me through their word; that they all may be one; as thou, Father, art in me, and I in thee, that they may be one in us; that the world may believe that thou hast sent me." Now this leads me to consider more particularly the nature of this oneness which is essential for such a successful mission as will convince the world of the truth of Christ's mission from the Father. What is meant by this oneness, or this union? We are guided in our inquiry by three features which characterize it. First, It is a oneness such as subsists between Christ and God; secondly, It is a oneness which can be seen or appreciated; thirdly, It is a oneness which is calculated from its nature to convince the world of the truth of Christ's mission.