See also my posts on the D&Cs, including the 2021 “Come Follow Me” LDS Series.
For easy reference, here are the links to various early printed Mormon literature from the Joseph Smith Papers Project, if you want to compare and contrast to the modern D&Cs; see also “Changes to the D&Cs“:
- Revelations printed in The Evening and the Morning Star, June 1832–June 1833
- Book of Commandments, 1833
- Appendix: Proposed Sixth Gathering of the Book of Commandments
- Oliver Cowdery’s Copy of the Book of Commandments
- Doctrine and Covenants, 1835
- Revelations printed in Evening and Morning Star, January 1835–June 1836
- Doctrine and Covenants, 1844
D&C 129 is short (only 9 verses), and is about the “three grand keys” by which you can know whether someone is an angel, the spirit of a just man made perfect, or a devil pretending to be an angel of light. You’re supposed to be able to check by asking him to shake hands with you. If he’s an actual angel, he’ll shake hands and you’ll feel his hand; if he’s a spirit, he won’t move (i.e., he won’t try to shake your hand) because it would be considered deceptive and as a righteous spirit, he can’t deceive; but if he’s a devil, he’ll try to shake hands with you, but you won’t feel anything.
There is no evidence that JS or anybody else ever used this method to distinguish between angels, good spirits, and devils, so it seems a worthless revelation. Even worse, it can be used by knowledgeable people to deceive. Here’s how: a man can go to an LDS, and claim to have a message from God. This D&C instructs the LDS to try to shake hands with any claimed messenger. If he does this, the LDS will feel his hand — because he’s a human — but this supposedly confirms that the man is actually an angel!
I would also point out that v1-3 necessarily identifies Heavenly Father and Jesus as angels because it says that there are two kinds of beings in heaven, either angels (who are resurrected personages, and have bodies of flesh and bones), or “the spirits of just men made perfect” which are “not resurrected”. Since Jesus is certainly resurrected, and LDS theology holds that Heavenly Father was also “once a man who lived on another planet”, he must also be resurrected. Resurrected beings are all angels, according to this, which means that Jesus and Heavenly Father are angels!