ENOfficial
It was narrated that Harithah said: "I heard the Messenger of Allah (ﷺ) 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)."
Source: sunnah.com
Other translations
Arabic
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 " .
sunnah.com