This was said by the Blessed One, said by the Arahant, as I have heard:

"Bhikkhus, one thing arises in the world for the benefit of many people and for the happiness of many people. It arises for the sake of, for the benefit of and for the ease of of both gods and humans. What is this one thing? It is the harmony in the monastic community, unity within the Saṅgha. When the community is unified, bhikkhus, there are no mutual quarrels, no mutual abuse, no exclusion, and no abandonment of one another. In such a situation, those without confidence gain confidence, and those who have confidence increase their confidence."

The Blessed One spoke on this matter. In this regard, it is said:

"Harmony in the community brings ease, and supporting the unified brings further joy; One who enjoys unity and is firmly established in the Dhamma, does not fall away from peace and security; Having established the community in harmony, one rejoices in heaven for an aeon."

This matter too was spoken by the Blessed One, as I have heard.