Hadith on Charity: Every good deed is charity, even smiling at your brother

Jabir ibn Abdullah reported: The Messenger of Allah صلى الله عليه وسلم said, “Every good deed is charity. Indeed, it is good to meet your brother with a smiling face, and to pour what is left from your bucket into the vessel of your brother.”
[Sunan At-Tirmidhi, Book 25, Number 1970, Grade: Sahih]
Book of Righteousness, Chapter: What has been related about smiling and having a cheerful face

عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ قَالَ  قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كُلُّ مَعْرُوفٍ صَدَقَةٌ وَإِنَّ مِنْ الْمَعْرُوفِ أَنْ تَلْقَى أَخَاكَ بِوَجْهٍ طَلْقٍ وَأَنْ تُفْرِغَ مِنْ دَلْوِكَ فِي إِنَاءِ أَخِيكَ

قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ

سنن الترمذي كتاب البر والصلة عن رسول الله صلى الله عليه وسلم باب ما جاء في طلاقة الوجه وحسن البشر