This is one of the central paradoxes of the Gospel of Jesus Christ, since not harming others is important - but so is not stagnating by resisting necessary change (particularly through continuing revelation). Jesus of Nazareth certainly rocked the Jewish boat during his ministry; Martin Luther rocked the Catholic boat vigorously; Joseph Smith rocked the Protestant boat just as vigorously; the examples go on and on and on.
So, in summary:
"Rock the boat; don't rock the boat, baby. Rock the boat; don't tip the boat over (or cause undue, dangerous sickness to those in the boat)."
Sorry, couldn't resist.