Sometimes the very presence of the Holy Spirit within us brings conviction of sin to another, without our ever saying a word. This is especially true when we pray for that person. God’s love in us never abandons; it identifies deeply with individual people. But it also brings the reality of God‘s presence, the purity of his holiness. It is not intimidated by, nor does it flee from, the crisis of sin; neither does it deny the reality of sin’s existence. But sometimes it is the very love of God that demands that we speak painful truth to a friend.
–Rebecca Pippert
We are to live in such a way that shows Christ to others.
Simply doing so can bring conviction to them.
This is not a substitute for verbally sharing our belief in Jesus, rather it is a necessary complement to verbally sharing.
We are called to love others. That will sometimes require us to point out sin and speak painful truths. But that is also what we are called to do when someone is about to be run over by a bus. We point out the danger and speak the truth to keep them from being hit. And when we speak of eternity, sin can be much worse than a bus.