Sentence:  ...purſued his vnneighbourly purpoſe in ſuch ſort: that hee being the ſtronger perſwader, and ſhe (belike) too credulous in beleeuing or elſe ouer-feeble in reſiſting, from priuate imparlance, they fell to action; and continued their cloſe fight a long while together, vnſeene and vvithout ſuſpition, no doubt to their equall <WSD>ioy</WSD> and contentment. 
Meaning of the word marked with <WSD> tags:  A feeling of extreme happiness or cheerfulness, especially related to the acquisition or expectation of something good.