It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The muezzin is forgiven to the extent of his adhan, and every moist and dry thing that heard him bears witness for him." (b) It is also reported from Sayyiduna Abu Hurayrah (may Allah be pleased with him) as a marfu' narration. The first hadith is narrated by Hasan al-Basri from the Prophet (peace and blessings be upon him) as a mursal report.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2029