John Newton, the slave-ship captain and self-described chief of sinners turned wise and gracious Anglican pastor:
Of all people who engage in controversy, we, who are called Calvinists, are most expressly bound by our own principles to the exercise of gentleness and moderation.
If, indeed, they who differ from us have a power of changing themselves, if they can open their own eyes, and soften their own hearts, then we might with less inconsistency be offended at their obstinacy: but if we believe the very contrary to this, our part is, not to strive, but in meekness to instruct those who oppose.
“If peradventure God will give them repentance to the acknowledgment of the truth.” [2 Tim. 2:25, KJV]
If you write with a desire of being an instrument of correcting mistakes, you will of course be cautious of laying stumbling blocks in the way of the blind or of using any expressions that may exasperate their passions, confirm them in their principles, and thereby make their conviction, humanly speaking, more impracticable.
If you haven’t read his letter On Controversy, or reread it lately, it is so very helpful—to all of us.