Is it permissible for him to complete the purchase when he can hear the call to prayer?

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Should he pray in the mosque where there are some innovations or in the prayer-room in his building?
He did not pray in congregation because he was afraid that it would delay healing of his feet

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Related Answers:
He decided (and formed the intention) to carry on praying on his own because the sound of the imam’s voice was cut off, then the sound was restored, and he found that he had gone ahead of his imam in the prayer. What is the ruling?
If he enters the mosque when the imam has stood up from bowing, what should he say?
Can a woman say “Ameen” out loud when she is praying with her husband at home?
Should he pray in the mosque where there are some innovations or in the prayer-room in his building?
He did not pray in congregation because he was afraid that it would delay healing of his feet

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