Using the power of our words in debate can be a good thing if the other person is wrong and needs correction in an area of his or her life that will help them–or create a better relationship with the person with an opposing viewpoint. I'm talking about debate on a more personal, one-on-one level than in the public forum.
Being opinionated is okay, and using our words to persuade people towards a more positive direction in their lives is important. We just have to be careful that we are presenting our arguments justly and with the right attitude on our part. There can be a fine line between constructive criticism and judging others. And it is also better to correct someone's wrong views when necessary rather than to flatter or compliment them just to keep the peace.
In the end, people appreciate honest criticism far more than flattery. – Proverbs 28:23, NLT
As far as opening our mouths and letting the power of our words persuade people to our way of thinking, here are a couple of good Solomon sayings to consider:
Do not answer a fool with his own stupidity, or you will be like him. Answer a fool with his own stupidity, or he will think he is wise. – Proverbs 26:4,5, GW
Like a gold ring and a fine gold ornament, so is constructive criticism to the ear of one who listens. – Proverbs 25:12, GW
It seems to depend on the character of the individual we disagree with as to whether or not it is worth the time to express our opposing viewpoint. Like Jesus also said: "Don’t give what is holy to dogs or toss your pearls before pigs, or they will trample them with their feet, turn, and tear you to pieces." (Matthew 7:6, HCSB) That is, such people will not respect you or recognize the value of your opinion. They will just argue back with foolishness.
We should also respect other people's views even if we are opinionated. All of us should know how to keep quiet and listen to others–without getting red in the face about it.
My dearly loved brothers, understand this: Everyone must be quick to hear, slow to speak, and slow to anger, for man’s anger does not accomplish God’s righteousness . – James 1:19,20, HCSB
Whether we think someone is right or wrong, we must know how to control our tongues so the power of our words do not end up injuring people instead. Constructive criticism has its place but not "judgmental criticism".
Don’t criticize one another, brothers. He who criticizes a brother or judges his brother criticizes the law and judges the law. …But who are you to judge your neighbor? – James 4:11,12, HCSB
But why do you judge your brother? Or why do you show contempt for your brother? For we shall all stand before the judgment seat of Christ. – Romans 14:10, NKJV
It's fine if we want to debate with people or try to correct something in their lives that we believe is wrong, but let us do it wisely and respectfully. We are all flawed individuals (James 3:2) and have our own share of wrong views. We are all learning throughout our lives and changing our own minds and paths as needed. So we must have a balance in our opinionated ways so we don't try to take a speck out of one person's eye while we have a log in our own eye." (Matthew 7:1-5)
Now available: The inescapable power of words VI, A tale of two hearts