Perception: Calling the Jews "blind fools"

When reading the "new testament" a perception was made. Jesus makes the bold statement that anyone who calls someone a "fool" will go to hell. An odd statement indeed, because a bit later, Jesus himself labels others as fools:

"But I say to you that anyone who is angry with a brother will be subjected to judgment. And whoever insults a brother will be brought before the council, and whoever says ‘Fool’ will be sent to fiery hell. - Matthew 5:22

Blind fools! Which is greater, the gold or the temple that makes the gold sacred? - Matthew 23:17