Sentence:  All hail, great master! grave sir, hail! I come / To answer thy best pleasure; be't to fly, / To swim, to dive into the fire, to ride / On the curl'd clouds, to thy strong bidding <WSD>task</WSD> / Ariel and all his quality. 
Meaning of the word marked with <WSD> tags:  To assign a task to, or impose a task on.