"The words of the prophet declare the solemn responsibility of those who are appointed as guardians of the church of God, stewards of the mysteries of God. They are to stand as watchmen on the walls of Zion, to sound the note of alarm at the approach of the enemy. Souls are in danger of falling under temptation, and they will perish unless God's ministers are faithful to their trust. If for any reason their spiritual senses become so benumbed that they are unable to discern danger, and through their failure to give warning the people perish, God will require at their hands the blood of those who are lost. AA 361.1"
"When I say unto the wicked, O wicked man, thou shalt surely die; if thou dost not speak to warn the wicked from his way, that wicked man shall die in his iniquity; but his blood will I require at thine hand."
EGW's passage echoes the warning in Ezekiel 33:8 about the responsibility of watchmen and the consequences of failing to warn the wicked. The concept of blood being required at their hands is a direct parallel.
"Let a man so account of us, as of the ministers of Christ, and stewards of the mysteries of God."
EGW uses the term 'stewards of the mysteries of God,' which is directly from 1 Corinthians 4:1. The broader context of responsibility aligns with the verse's meaning.
"It is the privilege of the watchmen on the walls of Zion to live so near to God, and to be susceptible to the impressions of His Spirit, that He can work through them to tell men and women of their peril and point them to the place of safety. Faithfully are they to warn them of the sure result of transgression, and faithfully are they to safeguard the interests of the church. At no time may they relax their vigilance. Theirs is a work requiring the exercise of every faculty of the being. In trumpet tones their voices are to be lifted, and never are they to sound one wavering, uncertain note. Not for wages are they to labor, but because they cannot do otherwise, because they realize that there is a woe upon them if they fail to preach the gospel. Chosen of God, sealed with the blood of consecration, they are to rescue men and women from impending destruction. AA 361.2"
"Thy watchmen shall lift up the voice; with the voice together shall they sing: for they shall see eye to eye, when the Lord shall bring again Zion."
The 'watchmen on the walls of Zion' imagery is directly linked to Isaiah 52:8. While EGW expands on the role of the watchmen, the core concept is clearly derived from this verse.