"But there is no union between the Prince of light and the prince of darkness, and there can be no union between their followers. When Christians consented to unite with those who were but half converted from paganism, they entered upon a path which led further and further from the truth. Satan exulted that he had succeeded in deceiving so large a number of the followers of Christ. He then brought his power to bear more fully upon these, and inspired them to persecute those who remained true to God. None understood so well how to oppose the true Christian faith as did those who had once been its defenders; and these apostate Christians, uniting with their half-pagan companions, directed their warfare against the most essential features of the doctrines of Christ. GC 45.1"
"Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?"
The EGW passage echoes the principle of not being unequally yoked with unbelievers, as stated in 2 Corinthians 6:14, and applies it to the context of Christians uniting with those only partially converted from paganism.
"Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it."
The EGW passage draws a parallel between the 'Prince of light' and the 'prince of darkness,' which aligns with the contrast between God and the devil presented in John 8:44.
"It required a desperate struggle for those who would be faithful to stand firm against the deceptions and abominations which were disguised in sacerdotal garments and introduced into the church. The Bible was not accepted as the standard of faith. The doctrine of religious freedom was termed heresy, and its upholders were hated and proscribed. GC 45.2"
"For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears; And they shall turn away their ears from the truth, and shall be turned unto fables."
The EGW passage describes a time when the Bible was not accepted and religious freedom was suppressed, mirroring the warning in 2 Timothy 4:3-4 about people turning away from sound doctrine and heaping up teachers to suit their own desires. The connection is strong and relevant.