give pause

verb1

1. •
   To cause (someone) to hesitate and think carefully about something, giving (the person) cause to be unsure or concerned about something.

   • I was going to put up the new logo, since a majority of people like it a little better than the old one, but the ferocity of those who think it's terrible gives me pause.
   • Here is a fact that will give you pause: some states do not publish the voting records of their legislators.