and to goodness, knowledge; 2 Peter 1:5b
Faith is foundational. Next comes goodness, and now knowledge. The knowledge that Peter was talking about here is closer to to the word discernment or discretion. As we grow in our faith and virtue, we are able to discern the right and wrong things to do in most situations. It doesn’t mean that we’ll actually do the right things; it just means we become more aware of them. The Holy Spirit has to help us with that.
The takeaway from this is that as we grow in Christ, we are growing in maturity (or should be). The more we are in tune with what the Holy Spirit is doing in our lives, the more we can place our faith in Him. The Christian life is treacherous and full of obstacles. We don’t always know what to do. While we can’t rely on the Spirit of God to give out outright answers, we can rely on Him to nudge us one way or another.
In regards to sin, what He tells us is a no-brainer: run, flee, don’t do it!
But for the non-essentials in life, it’s not always clear cut. That’s why we must lean in closer.