O Lord, I have trusted in thee, and I will trust in thee forever. I will not put my trust in the arm of flesh; for I know that cursed is he that putteth his trust in the arm of flesh. Yea, cursed is he that putteth his trust in man or maketh flesh his arm. (2 Nephi 4:34)
What is “the arm of flesh?” I have often heard people equate it with human reasoning. But in the context of most of the scriptures decrying the arm of flesh, it seems more closely aligned with depending on someone else rather than on God. For example (emphasis mine):
Thus saith the LORD; Cursed be the man that trusteth in man, and maketh flesh his arm, and whose heart departeth from the LORD. (Jeremiah 17:5)
But how far does this extend? Surely not to those whom God has appointed as our leaders, right? I mean, if God has chosen them, surely we can trust them? Not according to JST Mark 9:40-48. Italics represent material that is added to or changed from the KJV:
[Editor's comment: Cutting off an offending hand or foot is compared to eliminating associations which may lead one astray. (compare Mark 9: 43-48)]
40 Therefore, if thy hand offend thee, cut it off; or if thy brother offend thee and confess not and forsake not, he shall be cut off. It is better for thee to enter into life maimed, than having two hands, to go into hell.
41 For it is better for thee to enter into life without thy brother, than for thee and thy brother to be cast into hell; into the fire that never shall be quenched, where their worm dieth not, and the fire is not quenched.
42 And again, if thy foot offend thee, cut it off; for he that is thy standard, by whom thou walkest, if he become a transgressor, he shall be cut off.
43 It is better for thee, to enter halt into life, than having two feet to be cast into hell; into the fire that never shall be quenched.
44 Therefore, let every man stand or fall, by himself, and not for another; or not trusting another.
45 Seek unto my Father, and it shall be done in that very moment what ye shall ask, if ye ask in faith, believing that ye shall receive.
46 And if thine eye which seeth for thee, him that is appointed to watch over thee to show thee light, become a transgressor and offend thee, pluck him out.
47 It is better for thee to enter into the kingdom of God, with one eye, than having two eyes to be cast into hell fire.
48 For it is better that thyself should be saved, than to be cast into hell with thy brother, where their worm dieth not, and where the fire is not quenched.
This is a fascinating reworking of this passage that can be difficult to understand literally. And it is especially interesting that these verses caution against undue dependence upon those who are “appointed to watch over” us and those who are our standards. Strong language, spoken to the Twelve, who had already separated themselves from the Jewish leadership of the time.
This emphasizes the fallibilism inherent in Mormonism -- a fallibilism that many critics, as well as many members of the Church, do not acknowledge. And this isn't a trivial fallibilism, either; this is a fallibilism that has, potentially, very serious spiritual consequences: the danger of hell fire.
On the other hand, we do have those who are “appointed to ... show [us] light,” and have an obligation to “give heed” to their words (cf. D&C 21:4-5). How do we reconcile these things? Nephi instructs us (emphasis mine):
Cursed is he that putteth his trust in man, or maketh flesh his arm, or shall hearken unto the precepts of men, save their precepts shall be given by the power of the Holy Ghost. (2 Nephi 28:31)
Or, as J. Reuben Clark explained in his excellent talk, When Are the Writings and Sermons of Church Leaders Entitled to the Claim of Scripture?:
The question is, how shall we know when the things they have spoken were said as they were “moved upon by the Holy Ghost”? I have given some thought to this question, and the answer thereto, so far as I can determine, is: We can tell when the speakers are “moved upon by the Holy Ghost” only when we, ourselves, are “moved upon by the Holy Ghost.” In a way, this completely shifts the responsibility from them to us to determine when they so speak.
In the introduction to the Doctrine & Covenants (D&C 1), the Lord explains some of the purposes of the Restoration. In verses 19-20, we read:
The weak things of the world shall come forth and break down the mighty and strong ones, that man should not counsel his fellow man, neither trust in the arm of flesh—But that every man might speak in the name of God the Lord, even the Savior of the world; (D&C 1:19-20)
I believe this is made possible by the exercise of the gift of the Holy Ghost, which derives from the restored Melchizedek Priesthood. In this way, we can “let every man stand or fall, by himself, and not for another.”