With minor various, these paragraphs goes back to the 1784 Book of Discipline, the very first one. This is from the 1920, ME Book of Discipline
V. Necessity of Union Among Ourselves
138. Let us be deeply sensible (from what we have known) of the evil of a division in principle, spirit, or practice, and the dreadful consequences to ourselves and others. If we are united, what can stand before us? If we divide, we shall destroy ourselves, the work of God, and the souls of our people.
139. In order to a closer union with each other, 1. Let us be deeply convinced of the absolute necessity of it. 2. Pray earnestly for, and speak freely to, each other. 3. When we meet, let us never part without prayer. 4. Take great care not to despise each other’s gift*. 5. Never speak lightly of each other. 6. Let us defend each other’s character in everything so far as is consistent with truth. 7. Labor in honor each to prefer the other before himself. We recommend a serious perusal of The Causes, Evils, and Cures of Heart and, Church Divisions.
If you track this well enough, you will see that the 1784 version of the Book of Discipline largely goes back to John Wesley himself. Directly. The 1784 Book of Discipline was adopted largely from the Large Minutes of Wesley and his British societies. In other words, paragraph 139 was written by Wesley — except for the “We recommend…” part which seems to come from Asbury.
In looking at the Large Minutes (linked above), you cannot help but notice that Wesley strove for unity, not merely among those of the same theological persuasion, but so too of Christians.
If only we, as United Methodists, would work to that same goal — perhaps beginning with ourselves. Shoot, we aren’t even convinced that it is necessary.