Jacob takes pains to specify that he is not claiming this power (to move mountains) as a result of his own actions but rather explains but that it is Yahweh’s gift—a function of Yahweh’s grace.
Redaction: The phrase “showeth us our weakness that we may know” echoes a similar verse in Ether 12:27: “And if men come unto me I will show unto them their weakness. I give unto men weakness that they may be humble; and my grace is sufficient for all men that humble themselves before me; for if they humble themselves before me, and have faith in me, then will I make weak things become strong unto them.” Despite the similarity, Jacob was not referring to this statement, for the Jaredite records would not enter the Nephite world for another two hundred years. Jacob, like his prophetic counterpart, was aware of the principle, but the similarity of language, as well as thought, was probably influenced by the translation process.
Joseph Smith was obviously influenced by outside sources in translating the text on the plates. The Bible was his most frequent model for language. His contemporary culture supplied phrases and explanatory context. In this case, however, the similarity of phrase may have come from his earlier translation.
When Martin Harris lost the 116 manuscript pages, Joseph, after a period of repentance, began translating again. Where did he begin? The best evidence suggests that rather than beginning with the replacement text represented by the small plates which God had inspired Mormon to include untouched in his own record (W of M 1:3–7), Joseph continued with the large plate material (the book of Mosiah), only later using the small plates text to tell again the lost story of Lehi and his family. If this translation sequence is correct, then Joseph would have known of the phrase from Ether. Thus, the similar phrases in Jacob and in Ether are linked through Joseph rather than through the plates.