Acts 20:20:

And how I kept back nothing that was profitable unto you, but have shewed you, and have taught you publickly, and from house to house,

See also:

Don't Preach a D- Gospel
Balance: Avoiding Ditches on Either Side of the Road
Is It Ever Right to “Hold Back” on Preaching Divine Healing?
Objection: Healing Evangelists Are Unbalanced Because They Talk About Healing All the Time When There Is So Much Else in the Bible