It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "Whoever is shown kindness should repay it. If he has nothing with which to repay it, then he should at least say good words in praise of the one who did the kindness. Thus, whoever has said good words has expressed gratitude for it, and whoever conceals that kindness has shown ingratitude. And whoever displays a quality for himself which he does not possess has put on two garments of falsehood."
Hadith Referenceالادب المفرد / كتاب / 215
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : أخرجه أبوداؤد ، كتاب الأدب ، باب فى شكر المعروف : 4813 و الترمذي : 2034 - صحيح الترغيب : 968 و الصحيحة : 617»
It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever seeks refuge with you in the name of Allah, grant him refuge; and whoever asks you in the name of Allah, give to him; and whoever does a favor to you, repay him; and if you do not have anything to repay him with, then pray for him so much that it becomes known that you have repaid him."
Hadith Referenceالادب المفرد / كتاب / 216
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : أخرجه أبوداؤد ، كتاب الزكاة ، باب عطية من سأل بالله عز و جل : 1672 و النسائي : 2567 - الصحيحة : 254»