Final answer:
The literary device in the given sentence is a metaphor that illustrates a dramatic change or realization about a person as if they are being 'born' into a new state of being with purpose.
Step-by-step explanation:
The literary device used in the sentence 'he came alive to me, suddenly delivered from the womb of his purposeless splendor' is a metaphor. This metaphor compares a significant change or realization about a person to a birth, implying a dramatic transformation or awakening to new qualities or aspects of this person that were previously unnoticed or unrecognized. This device evokes a strong image of someone emerging with a newfound purpose or clarity.