Abu Dharr reported: The Messenger of Allah, peace and blessings be upon him, said:

لاَ تَحْقِرَنَّ مِنَ الْمَعْرُوفِ شَيْئًا وَلَوْ أَنْ تَلْقَى أَخَاكَ بِوَجْهٍ طَلْقٍ

Do not regard any good deed as insignificant, even meeting your brother with a cheerful face.

Source: Sahih Muslim 2626, Grade: Sahih
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Adi ibn Hatim reported: The Messenger of Allah, peace and blessings be upon him, said:

اتَّقُوا النَّارَ وَلَوْ بِشِقِّ تَمْرَةٍ فَمَنْ لَمْ يَجِدْ فَبِكَلِمَةٍ طَيِّبَةٍ

Protect yourself from the Hellfire even with half of a date in charity, and if he cannot find it then with a kind word.

Source: Sahih Bukhari 6195, Grade: Muttafaqun Alayhi

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