It was known that Imām Mālik was a staunch adversary to innovations in the religion. This has been well documented from Imām Mālik himself, his students, other scholars and historians. Here are a few exemplifications of this uncontested fact. 

Ibn Waḍḍāh al-Qurṭubī mentioned, “Mālik used to despise every innovation, even if it was (supposedly) in good.” 

This is similar to the statement of Ibn Mājishūn who stated, “I heard Mālik say, ‘Anyone who innovates an innovation in the religion of Islām and he deems it as being good has made the assertion that Muḥammad (صلى الله عليه وسلم) has betrayed the message he was sent with. This is because Allāh, the Most High, states, {Today, I have completed your religion for you}, [al Mā‘idah:3]. Therefore, whatever was not part of the religion (during the time of the Prophet and his Companions), is not a part of the religion today.’”2

1 Al Bid’ah wa an Nahī ‘anhā, pg. 58.
2 Al ‘Itisām of al Imam as Shātibī, pg. 49, v.1).