Amīr al-mu'minīn Imam Ali (as), peace be upon him, said about those who avoided fighting on his side:
They abandoned right
but did not support wrong.10
10. This saying is about those who claimed to be neutrals, such as 'Abdullah ibn 'Umar, Sa'd ibn Abi Waqqas, Abu Musa al-Ash'ari, al-Ahnaf ibn Qays, Muhammad ibn Maslamah, Usamah ibn Zayd and Anas ibn Malik, etc. No doubt these people did not openly support wrong but not to support right is also a kind of support of wrong. Therefore, they will be counted among the opponents of right.