All 3 Uses

doctrine
in
Utopia, by Thomas More
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The greatest parts of His precepts are more opposite to the lives of the men of this age than any part of my discourse has been, but the preachers seem to have learned that craft to which you advise me: for they, observing that the world would not willingly suit their lives to the rules that Christ has given, have fitted His doctrine, as if it had been a leaden rule, to their lives, that so, some way or other, they might agree with one another.†
*
We know how religiously they are observed in Europe, more particularly where the Christian doctrine is received, among whom they are sacred and inviolable!†
After they had heard from us an account of the doctrine, the course of life, and the miracles of Christ, and of the wonderful constancy of so many martyrs, whose blood, so willingly offered up by them, was the chief occasion of spreading their religion over a vast number of nations, it is not to be imagined how inclined they were to receive it.†

Definitions:

(1) (doctrine)
a belief (or system of beliefs or principles) accepted as authoritative by some group
(2) (meaning too rare to warrant focus)