Sayyiduna Jabir (may Allah be pleased with him) said: Whoever tells you that the Messenger of Allah (peace and blessings be upon him) used to address the people from the pulpit while sitting, call him a liar. Sayyiduna Jabir (may Allah be pleased with him) said: And I myself am a witness that he (peace and blessings be upon him) would deliver the sermon standing, then sit, then stand and deliver the second sermon. The narrator said: I asked: "How was his (peace and blessings be upon him) sermon?" He said: "It was speech with which he (peace and blessings be upon him) admonished the people, and he would recite verses from the Book of Allah, and it was moderate. And his (peace and blessings be upon him) prayer was moderate too, roughly the length of the surah 'Wash-shamsi wa duhaha' and the surah 'Was-sama'i wat-tariq', except for the Fajr and Zuhr prayers. Sayyiduna Bilal (may Allah be pleased with him) would call the adhan as soon as the sun passed its zenith, and sometimes he would delay the iqamah a little and sometimes hasten it, but the adhan never deviated from the time. Asr was roughly as you pray it, Maghrib likewise roughly as you pray it, and he would pray Isha a little later than your prayer."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 2038