Neither pray I for these alone, but for them also which 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 also may be one in us; that the world may believe that thou hast sent me. John 17:20, 21. YRP 86.1
Harmony and union existing among men of varied dispositions is the strongest witness that can be borne that God has sent His Son into the world to save sinners. It is our privilege to bear this witness. But, in order to do this, we must place ourselves under Christ's command. Our characters must be molded in harmony with His character, our wills must be surrendered to His will. Then we shall work together without a thought of collision. YRP 86.2
Little differences dwelt upon lead to actions that destroy Christian fellowship. Let us not allow the enemy thus to gain the advantage over us. Let us keep drawing nearer to God and to one another. Then we shall be as trees of righteousness, planted by the Lord, and watered by the river of life. And how fruitful we shall be! Did not Christ say: “Herein is my Father glorified, that ye bear much fruit” (John 15:8)? YRP 86.3
The heart of the Saviour is set upon His followers’ fulfilling God's purpose in all its height and depth. They are to be one in Him, even though they are scattered the world over. But God cannot make them one in Christ unless they are willing to give up their own way for His way. YRP 86.4
When Christ's prayer is fully believed, when its instruction is brought into the daily life of God's people, unity of action will be seen in our ranks. Brother will be bound to brother by the golden bonds of the love of Christ. The Spirit of God alone can bring about this oneness. He who sanctified Himself can sanctify His disciples. United with Him, they will be united with one another in the most holy faith. When we strive for this unity as God desires us to strive for it, it will come to us.—Testimonies for the Church 8:242, 243. YRP 86.5