Is it wrong for a 19 yr to date a 38 yr old?

Age and its relation to relationships is a social thing, in some places or to some people it may be OK and in other places it would be a big no-no. It would really depend on the environment of the two and if they're willing to accept the view of the society which opposes such an action. Personally, I think it really comes down to compatibility and of course the larger the age gap the less compatibility.