Christian courtesy is vital kindness in a marriage's tense times. Listening without interrupting. Refraining from namecalling. Allowing the other person to speak his piece. Living by a rule of courtesy enables us to keep inevitable anger from overflowing into rage.
Uncontrolled anger blocks kindness.
But persistent exercise of Christian confrontation, forgiveness, and courtesy enables the fruit of kindness to lend its sweetness to a marriage. Even a difficult marriage. Anyone can return kindness with kindness. We lived in malice and envy, being hated and hating one another. Then comes the good news.