Being an adopted son does not make a place one’s original homeland (watan asli)
Question
A man travelled approximately three hundred miles from Deoband; in the place he went to he is an adopted son (mutabanna) of that place, and he intends to stay there eight or nine days. Must this man pray the full prayer during his stay, or will he perform qasr? What is the ruling if this man leads the prayer forgetfully? And what is the ruling if he leads the prayer deliberately? Is the ruling the same in both cases or different?
Answer
If that place is not his original homeland (watan asli), then in the case described he will perform qasr and will not pray in full (itmam). His leading the prayer is permissible, but he should perform qasr: if he prays in full, the prayer of the resident (muqim) followers will not be valid.
Source: Fatawa Mahmudiyya
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