A traveller joined two prayers together at the time of the earlier one, then he went back to his city before the time for the later prayer began

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Shortening the prayer when returning from cancelled travel plans
At what point is a traveler permitted to commence shortening the prayers

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Related Answers:
They are travelling to a European country and there are 15 of them; should they pray Jumu ‘ah?
A woman should not travel except with a mahram, even if it is a short trip
He is traveling and joining the prayers is easier for him
Shortening the prayer when returning from cancelled travel plans
At what point is a traveler permitted to commence shortening the prayers

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