Even if two mosques are close together, the adhan should be called in both

Question

Two mosques are very close to each other; the adhan of one mosque can be heard at the other. Is it sufficient to call [the adhan] in only one of the mosques or not? If it is not sufficient, will the people of the second mosque, in which the adhan was not called, be sinful or not?

Answer

It is sunna to call a separate adhan in each of the two mosques; to suffice with only one is contrary to the sunna. Those who do so will be abandoners of the sunna.

Source: Fatawa Mahmudiyya

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