John Piper from 2001:
It seems to me that we are always falling off the horse on one side or the other in this matter of being tough and tender — wimping out on truth when we ought to be lion-hearted, or wrangling with anger when we ought to be weeping. I know it's a risk to take up this topic and John Newton in a setting like this, where some of you need a good (tender!) kick in the pants to be more courageous, and others of you confuse courage with what William Cowper called "a furious and abusive zeal." Oh how rare are the pastors who speak with a tender heart and have a theological backbone of steel.
I dream of such pastors. I would like to be one someday. A pastor whose might in the truth is matched by his meekness. Whose theological acumen is matched by his manifest contrition. Whose heights of intellect are matched by his depths of humility. Yes, and the other way around! A pastor whose relational warmth is matched by his rigor of study, whose bent toward mercy is matched by the vigilance of his biblical discernment, and whose sense of humor is exceeded by the seriousness of his calling.
I dream of great defenders of true doctrine who are mainly known for the delight they have in God and the joy in God that they bring to the people of God — who enter controversy, when necessary, not because they love ideas and arguments, but because they love Christ and the church.
Excerpt from John Newton: The Tough Roots of His Habitual Tenderness.