Bible Teacher Duffy Robbins teaches from Ephesians 4:26–27 and 30–32, reminding us that not all anger is sin — but unchecked anger is one of the enemy's most effective weapons. Duffy unpacks how unholy anger works: it starts small but grows fast, it begins inside us but eventually poisons everything around us, and it always brings grief — to our relationships and to the Holy Spirit Himself. The good news is that the same God who calls us to "be angry and do not sin" has also given us the power, through His Spirit, to kill bitterness at the root before it takes over.