[342]Sanctification, then, is to be made holy, in the likeness of our Lord. Concerning such Jesus said: "Sanctify them through thy truth; thy word is truth". (John 17:17) The Christian now must feed upon or study the Word of God, learn its principles, learn of Jehovah's character and that of the Lord Jesus, and strive to conform his own life thereto. He now has set before him the hope of being made like the Lord in glory; and "every man that hath this hope in him purifieth himself, even as he is pure". (1 John 3:3) This process of sanctification is done by the Lord through his Word. "Both he who sanctifies and those whom he is sanctifying have all one Father, and for this reason he is not ashamed to speak of them as brethren." (Hebrews 2:11, _Weymouth_) Here we see the sanctifier is the Lord Jesus Christ, and those whom he is sanctifying are the members of his body; and all of these have one Father, Jehovah God; therefore all of the one body, constituting the mystery of God. [343]All this work of sanctification is done in what we designate the school of Christ; and it is only those who are in this school by being in Christ Jesus that can be sanctified and ultimately be a part of that glorious mystical body, the heavenly kingdom class that will constitute the great prophet, priest, and king. [344]This mystery hid from ages and generations and made known only to the saints is, says the apostle Paul, the Christ; and the Christ in you is the hope of glory. Those who are in Christ and who have the spirit of Christ in them have the glorious hope of being born on the divine plane as members of the body of Christ. These are called to the obtaining of the glory of our Lord Jesus Christ; and to them are given all the exceeding great and precious promises contained in the Word of God. The Prophet speaking of them and to them said: "The nations shall see thy righteousness, and all the kings thy glory: and thou shalt be called by a new name, which the mouth of the Lord shall name. Thou shalt also be a crown of glory in the hand of the Lord, and a royal diadem in the hand of thy God." (Isaiah 62:2,3) These have the promise: "When Christ, who is our life, shall appear, then shall ye also appear with him in glory". (Colossians 3:4) And "then shall the righteous shine forth as the sun in the kingdom of their Father".--Matthew 13:43.