A simple yet profound proverb. I am 99.9% on the hidden love side (that is probably a generous percentage; it should be closer to 100%). I hardly ever rebuke anyone (and I haven't been rebuked very much). My love for people around me is hidden when it comes to confronting.
Why is an open rebuke better than hidden love?
1. Hidden love is motivated by selfishness (an unwillingness to take a risk for the sake of a fellow Christian).
2. Hidden love disregards the gospel and Christ's sacrifice for sins.
3. Hidden love does not take sin seriously.
4. An open rebuke at least opens the door to repentance.
5. Hidden love creates shallow relationships and does not build the community of faith.