if the mountain won't come to Mahomet

If the mountain won’t come to Mahomet, Mahomet will/must go to the mountain (The saying advises swallowing one's pride in order to take the initiative is something.) — если гора не идет к Магомету, (то) Магомет идет к горе

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Mohammed (570-632 AD) was the founder of Islam, the Muslim religion.

The story behind the saying is that when people asked Mohammed to give miraculous proof of his teaching he ordered a mountain to move towards him; when it did not do so he used the incident as a lesson that God had spared them from destruction by the mountain, and he went to it to offer thanks for God's mercy.

The story first appeared in English in Francis Bacon's Essays ('On Boldness', 1625) to illustrate boldness in an orator or leader, not with the interpretation now placed on it.