'Of the seven deadly sins, anger is possibly the most fun. To lick your wounds, to smack your lips over grievances long past, to roll over your tongue the ...'
Anger can be outwardly visible, but it can also show up in ways that are subtle, indirect, and deceptive. Proverbs 26:24-26 provides an example of this.
'Passive-aggressive' behavior is hidden anger, including intentional inefficiency, obstruction, procrastination, and showing irritation by not conforming.
Unrighteous anger, whether explosive or smoldering, can lead to high blood pressure, migraine headaches, or can ultimately lead to our spiritual demise.
We dare not let the sun go down on our wrath. Uncontrolled anger can be a major cause of mental and physical illness. We must reconcile with our adversaries.
Righteous anger is unselfish. Sinful anger occurs when our desires, ambitions, or demands are not met, always focusing on satisfying the self.
James' exhortation about the use of the tongue seems to stop with James 3:12. However, the rest of the chapter provides more wisdom on controlling our speech.