The Quran

Preface

إِنَّمَا المُؤمِنونَ الَّذينَ آمَنوا بِاللَّهِ وَرَسولِهِ وَإِذا كانوا مَعَهُ عَلىٰ أَمرٍ جامِعٍ لَم يَذهَبوا حَتّىٰ يَستَأذِنوهُ ۚ إِنَّ الَّذينَ يَستَأذِنونَكَ أُولٰئِكَ الَّذينَ يُؤمِنونَ بِاللَّهِ وَرَسولِهِ ۚ فَإِذَا استَأذَنوكَ لِبَعضِ شَأنِهِم فَأذَن لِمَن شِئتَ مِنهُم وَاستَغفِر لَهُمُ اللَّهَ ۚ إِنَّ اللَّهَ غَفورٌ رَحيمٌ

Yusuf Ali

Only those are believers, who believe in God and His Messenger. when they are with him on a matter requiring collective action,¹ they do not depart until they have asked for his leave; those who ask for thy leave are those who believe in God and His Messenger. so when they ask for thy leave, for some business of theirs, give leave to those of them whom thou wilt,² and ask God for their forgiveness:³ for God is Oft-Forgiving, Most Merciful.

Matter requiring collective action: anything that affects the Community as a whole: fumu'ah and 'Id prayers are periodical occasions of this kind, but what is meant here is, I think, joint consultations with a view to joint undertakings, such as Jihad, or some kind of organisation in peace.
That is, those to whom, in the exercise of your impartial discretion, you think it expedient to give leave. “Will”, unless the context shows otherwise, means “right will”, not a will without any definite principle behind it.
In important matters of general consultation, even though leave of absence is given on sufficient excuse, it implies some defect in duty on the part of the person to whom the leave is given, and therefore the need of forgiveness from Him to Whom we owe duty is a perfect measure.