1758/1 - Abu al-Juhaym ‘Abdullah ibn al-Hārith ibn al-Simmah al-Ansāri (may Allah be pleased with him) reported that the Messenger of Allah (may Allah’s peace and blessings be upon him) said: “If the one passing in front of a praying person knew the gravity of his act, he would prefer to stand for forty than to pass in front him.” The narrator said: “I do not know whether he said forty days, months, or years.” [Narrated by Al-Bukhāri and Muslim]
1) It is prohibited to pass in front of a praying person, whether the prayer is obligatory or supererogatory, whether he is praying in the mosque or elsewhere, and whether he is in Makkah or any other city.
2) Passing in front of a praying person is prohibited because it disrupts his focus and sense of devotion towards his Lord, and because he is entitled to the area between him and the Sutrah (screen), and so it is not permissible for anyone to encroach upon it.