The antonyms for "art steadfast" are words that describe inconsistency or lack of commitment. These include fickle, wavering, capricious, erratic, vacillating, indecisive, and unstable. A fickle person may be easily swayed by changing circumstances or emotions, while a wavering individual cannot make up their mind. Capricious people act on whim or fancy, and erratic individuals are unpredictable. Vacillating people have trouble sticking to one decision, while indecisive people take a long time to make up their minds. The opposite of being steadfast in dedication to one's beliefs or goals is to be unstable, easily distracted, or uncommitted.