What is the distance beyond which a person is not sinning if he passes in front of one who is praying?

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Check below answers in case you are looking for other related questions:
Covering the head during prayer
Jalsah al-Istiraahah (Sitting for a brief rest during prayer)

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Related Answers:
Should a traveller pray Sunnah?
He is assailed by doubts because he no longer focuses on his prayer
Moving the forefinger during the Tashahhud
Covering the head during prayer
Jalsah al-Istiraahah (Sitting for a brief rest during prayer)

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