Verse 19 returns even closer to the Isaiah source, from Isaiah 29:12: “And the book is delivered to him that is not learned, saying, Read this, I pray thee: and he saith, I am not learned.” The visit to Dr. Mitchell and Dr. Anthon had happened before the process of translation had begun, and the best indication is that even after the loss of the 116 pages, the translation picked up in Mosiah. Thus, this part of Nephi’s text had seen its fulfillment months prior, and had time to be processed.
The most important result of Martin Harris’s trip to the scholars was that the translation would not occur through the scholarly world. It would come through the unlearned, and Joseph Smith understood that he fit that description. He would need to learn another way to translate, and he did. Although the scholars could not do it, God declares in verse 20, “I am able to do mine own work; wherefore thou shalt read the words which I shall give thee.
This is no longer prophecy as much as direct communication to Joseph. It is Joseph who would literally read the words which God would give him to be able to dictate the translation. Even though Joseph had already been doing this by the time this verse was translated, it must still have come as an important confirmation of the way in which he was accomplishing the task that had been given to him.