I wonder if a man handing another man an extremely sharp, polished, two-edged instrument would hand it over with the air, gestures, and expression of one delivering a bouquet of flowers? Would not this be madness? What does one do then? Convinced of the excellence of the dangerous instrument, one recommends it unreservedly, to be sure, but in such a way that in a certain sense one warns against it. So it is with Christianity. If what is needed is to be done, we should not hesitate, aware of the highest responsibility, to preach in Christian sermons - yes, precisely in Christian sermons - against Christianity." - Soren Kierkegaard's (Works of Love: Some Christian Reflections in the Form of a Discourse)
I am reminded of Hebrews 4.12 (click here to read it in English Standard Version).