What does the Bible say about disagreement?
…until we all reach unity in the faith and in the knowledge of the Son of God and become mature, attaining to the whole measure of the fullness of Christ.
Then we will no longer be infants, tossed back and forth by the waves, and blown here and there by every wind of teaching and by the cunning and craftiness of people in their deceitful scheming.Instead, speaking the truth in love, we will grow to become in every respect the mature body of him who is the head, that is, Christ.Ephesians 4:13-15
These verses show us that Christian maturity includes (1) not believing false ideas, and (2) being able to “speak the truth in love.” That is, to be able to confront those whom you disagree with in a loving way.
In fact, to love someone is to act in their best interest, which means you want them to know the truth. A doctor, for instance, would hardly be a good physician if in an effort to not hurt your feelings hides your bad prognosis. If he thought you had cancer, a good physician would risk your feelings to get you on the right treatment plan. And we love doctors – especially those who get the right diagnosis in time to administer the cure. “Love does not delight in evil but rejoices with the truth.” (1 Cor 13:6). God is the good physician.
He is a God of love, so will always speak the truth, even though you may disagree. So even though we may disagree with someone, we can still be loving towards them. Augustine assumes this when he says a mature Christian should “embrace a mutual unity in things necessary; in things non necessary liberty; in all things charity.”