Musannaf Ibn Abi Shayba 3:2286

Zayd ibn al-Hubab narrated to us, from Yahya ibn al-Walid ibn al-Maysar al-Ta'i, who said: Muhall al-Ta'i informed me, from Adi ibn Hatim, who said: "Whoever leads us in prayer, let him complete the bowing (ruku') and the prostration (sujud), for among us are the weak, the elderly, the sick, the traveler, and the person with a need. This is how we used to pray with the Messenger of Allah, may Allah bless him and grant him peace."