Al-Mujadilah - ৫৮:১২

يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا نَاجَيْتُمُ الرَّسُولَ فَقَدِّمُوا بَيْنَ يَدَيْ نَجْوَاكُمْ صَدَقَةً ذَلِكَ خَيْرٌ لَّكُمْ وَأَطْهَرُ فَإِن لَّمْ تَجِدُوا فَإِنَّ اللَّهَ غَفُورٌ رَّحِيمٌ
[58:12]
O you who believe! when you consult the Messenger, then offer something in charity before your consultation; that is better for you and purer; but if you do not find, then surely Allah is Forgiving, Merciful.
O ye who believe! When ye consult the Messenger in private, spend something in charity before your private consultation. That will be best for you, and most conducive to purity (of conduct). But if ye find not (the wherewithal), Allah is Oft-Forgiving, Most Merciful.
O ye who believe! When ye hold conference with the messenger, offer an alms before your conference. That is better and purer for you. But if ye cannot find (the wherewithal) then lo! Allah is Forgiving, Merciful.