Spending is about time: day or night and manner: openly or secretly. So, don’t delay a charity you can give at night to daytime, and vice versa. Besides, don’t spend just openly but also in secret.
Reasons of revelation:
Ali Bin Abi Taleb (may Allah be pleased with him) once had four dirhams, and he spent one dirham at night, one during the day, one in secret, and one openly. Then this verse was revealed.
( فَلَهُمْ أَجْرُهُمْ عِندَ رَبِّهِمْ وَلَا خَوْفٌ عَلَيْهِمْ وَلَا هُمْ يَحْزَنُونَ … ) (…they will have their reward with their Lord. And no fear will there be concerning them, nor will they grieve): They get their rewards from Allah (swt), and no fear is there about their future because their future is in the hands of the Almighty for whom they work. There is no fear about them; they will never grieve in the afterlife. They won’t even be sad due to the feeling that their money has become less. In all, they won’t feel sad in the heart either in this life or in the afterlife as long as they are dealing with Allah (swt) in terms of charity, not with the poor.