The Bible sets before us a model church. They are to be in unity with each other, and with God. When believers are united to Christ, the living vine, the result is that they are one with Christ, full of sympathy and tenderness and love.—MS 21, 1893 (June 12); 3SM 18 PCL 47.2
Suppose Christ should abide in every heart and selfishness in all its forms should be banished from the church, what would be the result? Harmony, unity, and brotherly love would be seen as verily as in the church which Christ first established. Christian activity would be seen everywhere. The whole church would be kindled into a sacrificial flame for the glory of God. Every Christian would cast in the fruit of his self-denial to be consumed upon the altar. There would be far greater activity in devising fresh methods of usefulness and in studying how to come close to poor sinners to save them from eternal ruin.—5T 206 (1882) PCL 47.3
Those who are truly connected with God will not be at variance with one another. The spirit of harmony, peace, and love, His Spirit working in their hearts, will create harmony, love, and unity. The opposite of this works in the children of Satan; there is with them a continual contradiction. Strife, envy, and jealousy are the ruling elements. The characteristic of the Christian is the meekness of Christ. Benevolence, kindness, mercy, and love originate from infinite wisdom, while the opposite is the unholy fruit of a heart that is not in harmony with Jesus Christ.—MS 2, 1881 (December) PCL 48.1
One special evidence that the love of Christ is abiding in His church is the unity and harmony which exist among its members. This is the brightest witness to the possession of true religion; for it will convert and transform the natural man and fashion him after the divine similitude.—Letter 270, 1908 (September 23) PCL 48.2