Doctrine should definitely be a verb in the English language, but apparently, it is not. What would then be the word that best suits such a purpose?
Ex: He was doctrined to uphold such beliefs.
You are probably looking for
to instruct in a doctrine, principle, ideology, etc., especially to imbue with a specific partisan or biased belief or point of view.
(Dictionary.com)
He was indoctrinated to uphold such beliefs.
1620s, perhaps modeled on French endoctriner or extended from earlier (now obsolete) verb indoctrine, endoctrine, "to instruct" (mid-15c.); see in- (2) "in" + doctrine + -ate (2)).
(Etymonline)