Sahih Muslim 1008 a
Sa'id b. Abu Burda reported on the authority of his grandfather that the Messenger of Allah (ﷺ) said:
Giving of Sadaqa is essential for every Muslim. It was said (to him): What do you say of him who does not find (the means) to do so? He said: Let him work with both his hands, thus doing benefit to himself and give Sadaqa. It was said to him: What about him who does not have (the means) to do so? He said: Then let him assist the needy, the aggrieved. It was said: What do you say of one who cannot even do this? He said: Then he should enjoin what is reputable or what is good. He said: What about him if he cannot do that? He (the Holy Prophet) said: He should then abstain from evil, for verify that is Sadaqa on his behalf.
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ شُعْبَةَ، عَنْ سَعِيدِ بْنِ أَبِي، بُرْدَةَ عَنْ أَبِيهِ، عَنْ جَدِّهِ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏"‏ عَلَى كُلِّ مُسْلِمٍ صَدَقَةٌ ‏"‏ ‏.‏ قِيلَ أَرَأَيْتَ إِنْ لَمْ يَجِدْ قَالَ ‏"‏ يَعْتَمِلُ بِيَدَيْهِ فَيَنْفَعُ نَفْسَهُ وَيَتَصَدَّقُ ‏"‏ ‏.‏ قَالَ قِيلَ أَرَأَيْتَ إِنْ لَمْ يَسْتَطِعْ قَالَ ‏"‏ يُعِينُ ذَا الْحَاجَةِ الْمَلْهُوفَ ‏"‏ ‏.‏ قَالَ قِيلَ لَهُ أَرَأَيْتَ إِنْ لَمْ يَسْتَطِعْ قَالَ ‏"‏ يَأْمُرُ بِالْمَعْرُوفِ أَوِ الْخَيْرِ ‏"‏ ‏.‏ قَالَ أَرَأَيْتَ إِنْ لَمْ يَفْعَلْ قَالَ ‏"‏ يُمْسِكُ عَنِ الشَّرِّ فَإِنَّهَا صَدَقَةٌ ‏"‏ ‏.‏