Sunan an-Nasa'i, Volume 3, Book 23, Hadith 2556 (DarusSalam) ⓘ

It was narrated that Harithah said: "I heard the Messenger of Allah say: 'Give charity, for there will come a time when a man will walk about with his charity, and the one to whom he wants to give it will say: If you had brought it yesterday I would have accepted it, but today (I have no need of it)."

أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ مَعْبَدِ بْنِ خَالِدٍ، عَنْ حَارِثَةَ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏ "‏ تَصَدَّقُوا فَإِنَّهُ سَيَأْتِي عَلَيْكُمْ زَمَانٌ يَمْشِي الرَّجُلُ بِصَدَقَتِهِ فَيَقُولُ الَّذِي يُعْطَاهَا لَوْ جِئْتَ بِهَا بِالأَمْسِ قَبِلْتُهَا فَأَمَّا الْيَوْمَ فَلاَ ‏" ‏ ‏.‏