Did the Companions commit bid'ah (innovations) and muhdathat (new matters) in the religion, and should the creed be taken from them?

The Companions did not fall into innovations (bid'ah); rather, an innovation is defined as something that was not transmitted from them or from the Prophet, peace and blessings be upon him. What was reported from some individuals among them regarding an act of worship not transmitted from the Prophet, peace and blessings be upon him, would be due to ijtihad (definition) (independent reasoning) in understanding and applying a text, and not a recommended Sunnah (definition). Innovation (bid'ah) is everything that contradicts the Sunnah, or by which one seeks closeness to Allah when the Messenger has forbidden it, or which is not legislated except by a text and there is no text for it. Creed (Aqeedah) is taken from the Qur'an and Sunnah according to the understanding of the Companions, due to the Prophet's saying, "So عليكم بسنتي وسنة الخلفاء المهديين الراشدين (upon you is my Sunnah and the Sunnah of the rightly-guided Caliphs)" and his saying, "ما أنا عليه وأصحابي (what I and my Companions are upon)." The sayings of the Companions were in agreement regarding the Oneness of Allah and the fundamentals of religion; they did not differ on these as they differed on secondary matters. The imams of Hadith (definition) and Sunnah followed the methodology of the Companions in creed and recorded it in their books.