tror gör man i kyrkan

Swedish

"Believing is what you do in church" or "Believing is for church"

To assume or believe (a thing) is inferior to knowing (that same thing) for certain. Usually said in response to an uncertain or assumptive statement, to dismiss it as unhelpful.
"Matchen går inte bra hittills, men jag tror ändå att vi kommer att vinna." \ "Du tror? Tror gör man i kyrkan, jag tycker du ska spela bättre istället."
"The match is not going very well so far, but I still believe we will win." \ "You believe? Believing is for church, I think you should just play better."