Some relevant Bible verses on the matter...
Set a guard, O Lord, over my mouth;
Keep watch over the door of my lips.
Psalm 141:3
But now you yourselves are to put off all these: anger, wrath, malice, blasphemy, filthy language out of your mouth. - Colossians 3:8
Let no corrupt [unwholesome, rotten] word proceed out of your mouth, but what is good for necessary edification, that it may impart grace to the hearers. - Ephesians 4:29
But fornication and all uncleanness or covetousness, let it not even be named among you, as is fitting for saints; neither filthiness [obscenity], nor foolish talking, nor coarse jesting, which are not fitting, but rather giving of thanks. - Ephesians 5:3-4
There is righteous anger, but always be cautious (“Be angry, and do not sin”: do not let the sun go down on your wrath, nor give place to the devil. - Ephesians 4:26-27)
Now, that will always be tough in political board discussions. The natural tendency is to repay insult for insult. We're all capable of that. That doesn't lead to good discussion and certainly doesn't convince anybody, only to alienate. Some people aren't worth engaging with, "casting pearls before swine" and all that (Matthew 7:6). Sometimes you just have to be selective in choosing the battles in which to engage.
Finally, all of you be of one mind, having compassion for one another; love as brothers, be tenderhearted, be courteous; not returning evil for evil or reviling for reviling [insult for insult], but on the contrary blessing, knowing that you were called to this, that you may inherit a blessing. - 1 Peter 3:8-9
