Sayyiduna Jabir (may Allah be pleased with him) narrates that when the Prophet (peace and blessings be upon him) was ill, we prayed behind him while he was sitting. Sayyiduna Abu Bakr (may Allah be pleased with him) was saying the takbir after him, behind him, in order to convey his takbir to the people. The Messenger of Allah (peace and blessings be upon him) turned towards us, and on seeing us standing, he gestured to us to sit.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3415