"In my next vision I earnestly begged of the Lord that, if I must go and relate what He had shown to me, He would keep me from exaltation. Then He showed me that my prayer was answered, and if I should be in danger of exaltation His hand would be laid upon me, and I would be afflicted with sickness. Said the angel, “If you deliver the messages faithfully, and endure unto the end, you shall eat of the fruit of the tree of life and drink of the water of the river of life.” EW 21.1"
"Fear none of those things which thou shalt suffer: behold, the devil shall cast some of you into prison, that ye may be tried; and ye shall have tribulation ten days: be thou faithful unto death, and I will give thee a crown of life."
The angel's promise of eating from the tree of life and drinking from the river of life if EGW is faithful echoes the promise of a crown of life to those who are faithful unto death in Revelation 2:10. Both passages connect faithfulness with a reward in the afterlife. The confidence is slightly increased because of the specific mention of the tree of life, which is a significant symbol in Revelation.
"Soon it was reported all around that the visions were the result of mesmerism, [See Appendix .] and many Adventists were ready to believe and circulate the report. A physician who was a celebrated mesmerizer told me that my views were mesmerism, that I was a very easy subject, and that he could mesmerize me and give me a vision. I told him that the Lord had shown me in vision that mesmerism was from the devil, from the bottomless pit, and that it would soon go there, with those who continued to use it. I then gave him liberty to mesmerize me if he could. He tried for more than half an hour, resorting to different operations, and then gave it up. By faith in God I was able to resist his influence, so that it did not affect me in the least. EW 21.2"
"And no marvel; for Satan himself is transformed into an angel of light."
The EGW passage describes being accused of being influenced by mesmerism, which she identifies as being from the devil. The Bible verse states that Satan can transform himself into an angel of light, which is a form of deception. The connection is that both passages deal with deception and the influence of evil, although the specific context differs.
"If I had a vision in meeting, many would say that it was excitement and that someone mesmerized me. Then I would go away alone in the woods, where no eye or ear but God's could see or hear, and pray to Him, and He would sometimes give me a vision there. I then rejoiced, and told them what God had revealed to me alone, where no mortal could influence me. But I was told by some that I mesmerized myself. Oh, thought I, has it come to this that those who honestly go to God alone to plead His promises and to claim His salvation, are to be charged with being under the foul and soul-damning influence of mesmerism? Do we ask our kind Father in heaven for “bread,” only to receive a “stone” or a “scorpion”? These things wounded my spirit, and wrung my soul in keen anguish, well-nigh to despair, while many would have me believe that there was no Holy Ghost and that all the exercises that holy men of God have experienced were only mesmerism or the deceptions of Satan. EW 21.3"
"But thou, when thou prayest, enter into thy closet, and when thou hast shut thy door, pray to thy Father which is in secret; and thy Father which seeth in secret shall reward thee openly."
EGW describes going alone to pray to God in secret, and then being accused of mesmerism. The Bible verse encourages praying in secret. The connection is that both passages emphasize the importance of private prayer and communion with God, although the accusation of mesmerism adds a layer of complexity to the EGW passage.