And the Prophet (peace and blessings be upon him) said: If people knew the reward for giving the call to prayer (adhan), they would fight each other with swords to give the adhan.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 11241
Hadith Gradingحکم دارالسلام:إسناده ضعيف، وهو إسناد الرواية 11232