Lucy Walker recalls that Joseph saying he learned the "principle of plural marriage" in 1831.
Lucy Walker, United States Testimony 1892, Temple Lot Case, 450-451, MS 1160, Church History Library
27 Q: - State to the reporter as nearly as you can when you first heard of this principle of plural marriage, - that is, when you first heard it taught?
. . . .
A: - Well, in '42 was the time. That was the time that this principle was first taught, but it was revealed to the prophet in '31, but he did not teach it then only to a very few in whom he had confidence and felt he could trust absolutely, for he felt the importance and responsibility of the step he was taking.
. . . .
53 Q: - And yet you swear that he received a revelation on polygamy in 1831, notwithstanding the fact that you did not see him until 1841? Is that what you swear to mrs. Kimball? A: -Well that was his statement to me I know.