"***** Hope of the Church [From The Review and Herald , June 10, 1852 .] As I have of late looked around to find the humble followers of the meek and lowly Jesus, my mind has been much exercised. Many who profess to be looking for the speedy coming of Christ are becoming conformed to this world and seek more earnestly the applause of those around them than the approbation of God. They are cold and formal, like the nominal churches from which they but a short time since separated. The words addressed to the Laodicean church describe their present condition perfectly. (See Revelation 3:14-20 .) They are “ neither cold nor hot ,” but “ lukewarm .” And unless they heed the counsel of the “faithful and true Witness,” and zealously repent and obtain “gold tried in the fire,” “white raiment,” and “eye-salve,” He will spew them out of His mouth. EW 107"
"And unto the angel of the church of the Laodiceans write; These things saith the Amen, the faithful and true witness, the beginning of the creation of God; I know thy works, that thou art neither cold nor hot: I would thou wert cold or hot. So then because thou art lukewarm, and neither cold nor hot, I will spue thee out of my mouth. Because thou sayest, I am rich, and increased with goods, and have need of nothing; and knowest not that thou art wretched, and miserable, and poor, and blind, and naked: I counsel thee to buy of me gold tried in the fire, that thou mayest be rich; and white raiment, that thou mayest be clothed, and that the shame of thy nakedness do not appear; and anoint thine eyes with eyesalve, that thou mayest see. As many as I love, I rebuke and chasten: be zealous therefore, and repent. Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me."
Ellen White directly references Revelation 3:14-20 in this passage.
"So then because thou art lukewarm, and neither cold nor hot, I will spue thee out of my mouth."
EGW explicitly references Revelation 3:14-20 and quotes Revelation 3:16 directly, applying it to the condition of some Adventists.
"How much easier it would be to affect the heart and how much more would God be glorified if His servants were free from discouragement and trial, that they might with a free spirit present the truth in its beauty. Those who have been guilty of requiring so much labor of God's servants and burdening them with trials which belong to themselves to settle, will have to give account to God for all the time and means that have been spent to gratify themselves, thereby satisfying the enemy. They should be in a situation to help their brethren. They should never defer their trials and difficulties to burden a whole meeting, or wait until some of the messengers come to settle them; but they should get right before God themselves, have their trials all out of the way, and be prepared when laborers come to hold up their hands instead of weakening them. EW 107.1"
"Obey them that have the rule over you, and submit yourselves: for they watch for your souls, as they that must give account, that they may do it with joy, and not with grief: for that is unprofitable for you."
The EGW passage echoes the sentiment of Hebrews 13:17, focusing on the burden placed on spiritual leaders and the accountability of those who cause them grief. While not a direct quote, the principle of not hindering those who watch over souls is present.