To say that we need to stop talking about sex and start talking about Jesus makes two big errors.
First, it undervalues the power of sexual transgression to damage us as human beings and to damage our relationship with God. Our sexual instincts are so powerful and so central to our lives that they are integral to our personal identity. When we misuse our body by abandoning God’s instructions, it helps corrupt our self-understanding. It is actually cruel.
Furthermore, when we turn away from the living God, we replace him by the worship of idols. Again, this worship is often expressed and accompanied by sexual licence. Indeed we are living at a time when sexual permissiveness is the norm and there is no fear of God.
Second, it means that we cannot adequately summons people to repentance. Without the call to repentance there is no gospel. The great sin from which we need to repent is pride – lives directed by ourselves. But this great sin exhibits itself in idolatry, and idolatry often expresses itself in sexual sin as well as the horrors of greed and injustice and lack of love.