2. But He does not stop at this interior and invisible union between His disciples and Himself: He speaks likewise of a new and special command, and of a special gift, by which their union with each other should be known. "A[19] new command I give unto you, that you love one another: as I have loved you, that you also love one another. By this shall all men know that you are My disciples, if you have love one to another." And again, "This[20] is My command, that you love one another, as I have loved you. Greater love than this hath no man, that any one lay down his life for his friends.--These things I command you, that you love one another." But the Holy Spirit, whom our Lord was about to send forth, is the efficient principle of the love here enjoined, by His substantial indwelling, as we are told, "The[21] charity of God is poured forth in our hearts by the Holy Ghost who is given to us." From Him, therefore, bestowed by the Head of the Church, springs that unity of charity, which, being itself internal, is shown in outward signs, and constitutes that distinctive spirit of the Christian people, the spirit characterising it, and analogous to the national spirit in civil organization. 3. But our Lord likewise speaks of a third unity, springing from the direction of one and the same divine Spirit. "And[22] I will ask the Father, and He shall give you another Paraclete, that He may abide with you for ever: the Spirit of truth, whom the world cannot receive, because it seeth Him not, nor knoweth Him: but you shall know Him, because He shall abide with you, and shall be in you." "The Paraclete, the Holy Ghost, whom the Father will send in My name, He will teach you all things, and bring all things to your mind whatsoever I shall have said to you." "It[23] is expedient to you that I go: for if I go not, the Paraclete will not come to you; but if I go, I will send Him to you." "But when He, the Spirit of truth, is come, He will teach you all truth. For He shall not speak of Himself, but what things soever He shall hear, He shall speak; and the things that are to come, He shall show you. He shall glorify Me, because He shall receive of Mine, and shall show it to you." Of the nature of this unity we may judge by the gifts and offices assigned to that Spirit and Paraclete from whom it springs. Now He is repeatedly termed "the Spirit of truth," and His office, to _suggest_, to _announce_, to _teach_, and _to lead into all truth_. This unity, therefore, is opposed to the division produced by ignorance and error, and so is the unity of faith, or Christian profession. Thus our Lord promises, besides the unity of charity, that of faith, the efficient principle of which, as well as of the former, is contained in the communication of the Holy Spirit. But it is no less true in the supernatural order of divine gifts, than in the order of nature, that the first cause produces its effects by means of second causes. And here, as often as the Lord promises the