"Not all who feel that they have been called to preach, should be encouraged to throw themselves and their families at once upon the church for continuous financial support. There is danger that some of limited experience may be spoiled by flattery, and by unwise encouragement to expect full support independent of any serious effort on their part. The means dedicated to the extension of the work of God should not be consumed by men who desire to preach only that they may receive support and thus gratify a selfish ambition for an easy life. AA 354.1"
"For ye remember, brethren, our labour and travail: for labouring night and day, because we would not be chargeable unto any of you, we preached unto you the gospel of God."
Both passages address the idea that ministers should not be overly reliant on the church for financial support, and should be willing to work to support themselves. The EGW passage warns against those who preach only for support, while 1 Thessalonians 2:9 describes Paul's laboring night and day to avoid being a burden.