Antonyms for the phrase "took upon oneself" are numerous and include words such as avoided, declined, discouraged, deterred, dissuaded, rejected, refused and neglected. All of these alternatives suggest a lack of willingness to take on a responsibility or task, either by choice or as a result of external factors. The opposite of taking upon oneself a task or responsibility is to avoid or decline it. This could be for a variety of reasons, such as lack of skills or resources, a dislike for the task itself, or an unwillingness to add more work to an already overflowing schedule. Regardless of the reason, antonyms for taking upon oneself communicate hesitation or outright refusal.