From Chris Royston, weekly collaborator here at Into Spanish Translation Blog:

Here are two idioms describing a knowledgeable person:

"Sabe más que Merlín" literally translates to "He knows more than Merlin". In English we employ the phrase "He's a know-it-all", but note that this is pejorative. "Sabe latín (mucho latín)" means "He knows Latin (a lot of Latin)". The colloquial equivalent in English is "He's nobody's fool".

Thanks Chris! And now my two cents:

- In Spain I’ve often heard “Sabe más que Lepe”. I didn’t know there was also a version featuring Merlin...
- There’s a literal Spanish counterpart for “He’s a know-it-all” (“Es un sabelotodo”), which is also pejorative in Spanish. A more positive option is “Se las sabe todas”, literally “He knows them all”, meaning “He knows all the tricks” or “You can’t fool him/her”.

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