harm
not harm a hair of someone's head not cause someone the slightest harm.
out of harm's way in a safe place.
1996Frank McCourtAngela's Ashes Take down the Pope and hide him in the coal hole…where he won't be seen and he'll be out of harm's way.
wouldn't harm a fly: see wouldn't hurt a fly atfly.
there is no harm in - the course of action specified may not guarantee success but is at least unlikely to have unwelcome repercussions.
2013Washington Post There is no harm in preferring one fellow over another, of course. But there is some harm in suggesting … that their rival visions define the arc of our national history.