Al-Quran- Sura No(24), Ayat(62)

They only are the true believers who believe in Allah and His messenger and, when they are with him on some common errand, go not away until they have asked leave of him. Lo! those who ask leave of thee, those are they who believe in Allah and His messenger. So, if they ask thy leave for some affair of theirs, give leave to whom thou wilt of them, and ask for them forgiveness of Allah. Lo! Allah is Forgiving, Merciful.