"Writing and Traveling Soon after our return to Rochester, N. Y., my husband engaged in writing the book “Signs of the Times.” He was still feeble, and could sleep but little, but the Lord was his support. When his mind was in a confused, suffering state, we would bow before God, and in our distress cry unto Him. He heard our earnest prayers, and often blessed my husband so that with refreshed spirits he went on with the work. Many times in the day did we thus go before the Lord in earnest prayer. That book was not written in his own strength. LS 150"
"I can do all things through Christ which strengtheneth me."
The EGW passage explicitly states that the book was not written in her husband's own strength, but through God's support, which aligns with the idea of Philippians 4:13 that one can do all things through Christ who strengthens them.
"In the fall of 1853 we attended conferences at Buck's Bridge, N. Y.; Stowe, Vt.; Boston, Dartmouth, and Springfield, Mass.; Washington, N. H.; and New Haven, Vt. This was a laborious and rather discouraging journey. Many had embraced the truth who were unsanctified in heart and life; the elements of strife and rebellion were at work, and it was necessary that a movement should take place to purify the church. LS 150.4"
"Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us:"
Both passages deal with the need for purification within a religious community. EGW speaks of a movement to purify the church, while 1 Corinthians 5:7 urges believers to purge out the old leaven. The connection is thematic and meaningful.