Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) relates that he heard the Prophet (peace and blessings be upon him) say: "Accursed is the one who asks by means of the Face of Allah, and accursed is the one who is asked by means of Allah and then refuses the one asking him, as long as he has not asked for something evil."
Imam al-Tabarani recorded this narration from his teacher Yahya bin Uthman bin Salih, who is thiqah (trustworthy), and there is weakness in him; the remaining narrators of this narration are the narrators of the Sahih. (Allamah al-Haythami says:) I say: A hadith about the virtue of Sayyiduna al-Khidr (peace be upon him) has already passed before this, and some narrations about giving charity have passed in the Book of Zakah.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأدعية / 17241