One shouldn't be envious when others admire their lover. One should revel in seeing him or her be noticed.
Edward Petty's poetry is written by one man about his better half, who happens to be another man. It's all about how his lover not only completes him but mesmerizes him. It's all about how he's able to not be jealous of other men eyeing his lover's beautiful body but to welcome all the well-deserved flirtation that he receives.