You must search your deck in order to find an evil card in the deck, right?
You could also look at your deck to find an evil card as well. The context isn't clear on the card itself, that is why I ask.
Search is different from a "Look" like the Promo John or "Look and Take" like Susanna. Nazareth doesn't stop the "Look" or "Look and Take" abilities, only searches, of which Outpost is one. A Search attempts to find one card (or type of card) amongst
all of a location, whereas the other abilities look at a specified amount of a particular location. That you can also take in the case of Susanna and similar cards has still been ruled to be different than searching.
And as they are different, you can't do any part of the Search because the deck is protected. That includes even looking at it for an evil card.
Now, you could still discard Outpost itself to search your discard pile for a generic Philistine, but Nazareth does effectively stop Outpost otherwise.