In Alma 12:28, Alma speaks of Adam and Eve:
And after God had appointed that these things should come unto man, behold, then he saw that it was expedient that man should know concerning the things whereof he had appointed unto them;
Therefore he sent angels to converse with them, who caused men to behold of his glory.
Where did Joseph Smith get the idea that angels appeared to Adam and Eve?
Evidence Central notes how this is consistent with traditions found in obscure Jewish, Christian, Mandaean and Muslim texts:
Why would these texts agree with the Book of Mormon? How would Joseph Smith have known this about Adam and Eve?