1 Nephi 19:20

In verse 20, Nephi tells us about his gratitude to the Lord for teaching him, through the Holy Ghost, about the need to leave Jerusalem and their spirituality level.

He says that he has had many workings in the Spirit. I don't doubt that he did work to know the truthfulness of the words of his father. But the very nature of being under the influence of the Spirit to behold the things of God consumes in a sense one's physical strength, so much so that they need a period of recovery. The footnotes to verse 20 give us some examples.

My example is that of the first prophet of this dispensation, Joseph Smith. When he was 14, Joseph Smith saw Heavenly Father and Jesus Christ. It was a great experience. He prayed to know which church was true. As an answer to his prayer, They came and said to join none at the time. He would be the instrument through which they would restore the true church of Christ, the very same that existed when He walked the earth.

Here is a portion of Joseph Smith's words from his account in the Pearl of Great Price:

"20 He again forbade me to join with any of them; and many other things did he say unto me, which I cannot write at this time. When I came to myself again, I found myself ^alying on my back, looking up into heaven. When the light had departed, I had no strength; but soon recovering in some degree, I went home. And as I leaned up to the fireplace, ^bmother inquired what the matter was. I replied, 'Never mind, all is well—I am well enough off.' I then said to my mother, 'I have learned for myself that Presbyterianism is not true.'"

Later on in Joseph's life, he grew accustomed to this type of experience. He gained a strength to handle such intensely spiritual experiences. I remember that when he and Sidney Rigdon both received section 76 of the Doctrine and Covenants Sidney was like Joseph used to be. Here is a portion of the account of the experience as recorded by Philo Dibble:

"Joseph sat firmly and calmly all the time in the midst of a magnificent glory, but Sidney sat limp and pale, apparently as limber as a rag, observing which, Joseph remarked, smilingly, 'Sidney is not used to it as I am.'" (Juvenile Instructor, May 1892, pp. 303–4.)

In the end of verse 20, Nephi acknowledges the mercy of the Lord in sparing his life. He says that the Lord had preserved him from destruction by leading him out of Jerusalem.