Nafi' narrated that 'Abdullah bin 'Umar used to say:

"When the Muslims arrived in al-Madinah they used to gather and try to figure out the time for prayer, and no one gave the call to prayer. One day they spoke about that; some of them said: 'Let us use a bell like the Christians do;' others said, 'No, a horn like the Jews have.' 'Umar, may ,Allah be pleased with him, said: 'Why don't you send a man to announce the time of prayer?' The Messenger of Allah (sallallaahu alayhi wa sallam) said: 'O Bilal, get up and give the call to prayer.'"



It is makruuh to give the adhaan while one is seated. The Jurists agree upon this. There evidence is the above hadith. It says get up and give the call to prayer. Based on these words they have said that one is to give the adhaan while he is standing.

Abu Haamid was from the Hanbali school of thought. He said if a person gives the call to prayer while seated, then the adhaan will be void.



Reference(s):

Kuwaiti Encyclopedia of Fiqh
Volume 15 Page 264