en_tn/jas/04/15.md

we will live

the word "We" does not directly refer James or his Audience but as an example of how Jame's audience should behave.

we will do this or that

This could be translated as "do what we have planned to do."

to him who knows

James is not addressing anyone directly by the word "him", but to anyone who is to do good but does not.