The ruling on reciting aloud in the secret prayers and reciting quietly in the loud prayers

Question:
Honorable Shaykh. An imam recited quietly in a loud prayer and recited aloud in a secret prayer.

Answer:
Reciting aloud and reciting quietly is a recommended practice (sunnah), not obligatory. So if he recites aloud in a secret prayer, his prayer is valid because he left off a recommended practice. Or if he recites quietly in a loud prayer, his prayer is valid. Because reciting aloud at night and reciting quietly during the day is a recommended practice, not obligatory. And the Prophet (peace and blessings be upon him) would let his Companions hear some of the verses during the day, so there is nothing wrong with reciting some of the verses aloud, where he can hear what is being recited. But the day is specifically designated as quiet and the night as loud, and if he goes against this, his prayer is valid. Yes, and he is not required to perform the prostration for forgetfulness. Yes.