"into labor for the people, and this was exhausting their physical and mental strength. It was their duty to rest. GW 243.1"
"And he said unto them, Come ye yourselves apart into a desert place, and rest a while: for there were many coming and going, and they had no leisure so much as to eat."
Both passages emphasize the importance of rest for those engaged in labor. The EGW passage speaks of people exhausting their physical and mental strength and needing to rest, while Mark 6:31 describes Jesus telling his disciples to rest in a desert place. The connection is a clear thematic parallel.
"Christ's words of compassion are spoken to His workers today just as surely as to His disciples. “Come ye yourselves apart, ...and rest awhile,” He says to those who are worn and weary. It is not wise to be always under the strain of work and excitement, even in ministering to men's spiritual needs; for in this way personal piety is neglected, and the powers of mind and soul and body are overtaxed. Self-denial is required of the servants of Christ, and sacrifices must be made; but God would have all study the laws of health, and use reason when working for Him, that the life which He has given may be preserved. GW 243.2"
"And he said unto them, Come ye yourselves apart into a desert place, and rest a while: for there were many coming and going, and they had no leisure so much as to eat."
The EGW passage directly quotes Mark 6:31 and expands upon its meaning in the context of Christian workers. It's a clear and explicit allusion.
"Though Jesus could work miracles, and had empowered His disciples to work miracles, He directed His worn servants to go apart into the country and rest. When He said that the harvest was great and the laborers were few, He did not urge upon His disciples the necessity of ceaseless toil, but said, “Pray ye therefore the Lord of the harvest, that He will send forth laborers into His harvest.” [ Matthew 9:38 .] God has appointed to every man his work, according to his ability; and He would not have a few weighted with responsibilities, while others have no burden, no travail of soul. GW 243.3"
"Pray ye therefore the Lord of the harvest, that he will send forth labourers into his harvest."
Ellen White directly references Matthew 9:38 in this passage.