It is narrated from Sayyidah Aishah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) said: "The imam is a guarantor and the muezzin is entrusted; may Allah guide the imams and pardon the muezzin."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1997