This passage reminds us that the trouble we encounter when our faith is being tested will make us complete. It will build patience in our life and eventually make us perfect. It reminds us to move through trials with joy, the expectation of something wonderful.
This passage also reminds us we will face trials. There will be testing of our faith. Life will not always be perfect. Things won't always work out like we plan or how we want it to work out. But in the end, everything we go through will make us complete, perfect and lack nothing. It may not be easy, but it will be worth it all in the end.