For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are in conflict with each other, so that you are not to do whatever you want. (Galatians 5:17 NIV)
Initially I didn't know what did she mean by sharing it with me. But yesterday she told me that sometimes she struggled to follow God's will because of her human's weaknesses.
She also told me that she had been reading some articles about this. There was one particular part that had my interest, because it described the innate weaknesses of each of the four temperaments that could drag us to commit sins. It was like a coincidence it struck me, since I just wrote a blog post about these four temperaments a few days ago.
I forgot to ask her where to get the article, but basically I think I got the basic idea to reproduce them.