"Christ has given to the church a sacred charge. Every member should be a channel through which God can communicate to the world the treasures of His grace, the unsearchable riches of Christ. There is nothing that the Saviour desires so much as agents who will represent to the world His Spirit and His character. There is nothing that the world needs so much as the manifestation through humanity of the Saviour's love. All heaven is waiting for men and women through whom God can reveal the power of Christianity. AA 600.1"
"Unto me, who am less than the least of all saints, is this grace given, that I should preach among the Gentiles the unsearchable riches of Christ;"
Both passages refer to the 'unsearchable riches of Christ.' The EGW passage expands on this by describing how Christians can communicate these riches to the world, while Ephesians 3:8 focuses on Paul's role in preaching them to the Gentiles.
"Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost:"
The EGW passage elaborates on the 'sacred charge' given in Matthew 28:19, emphasizing the role of church members as channels for God's grace and representatives of Christ's character to all nations.
"Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ’s stead, be ye reconciled to God."
Both passages emphasize the role of believers as representatives of Christ. The EGW quote expands on the idea of being 'ambassadors for Christ' by highlighting the need to manifest Christ's love to the world.
"The church is God's agency for the proclamation of truth, empowered by Him to do a special work; and if she is loyal to Him, obedient to all His commandments, there will dwell within her the excellency of divine grace. If she will be true to her allegiance, if she will honor the Lord God of Israel, there is no power that can stand against her. AA 600.2"
"And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it."
Both passages speak of the church's invincibility when aligned with God's will. EGW expands on the conditions for this protection, echoing the sentiment of Matthew 16:18.
"Zeal for God and His cause moved the disciples to bear witness to the gospel with mighty power. Should not a like zeal fire our hearts with a determination to tell the story of redeeming love, of Christ and Him crucified? It is the privilege of every Christian, not only to look for, but to hasten the coming of the Saviour. AA 600.3"
"Looking for and hasting unto the coming of the day of God, wherein the heavens being on fire shall be dissolved, and the elements shall melt with fervent heat?"
The EGW passage directly references and expands upon the idea of 'hastening the coming of the Saviour,' which is explicitly mentioned in 2 Peter 3:12. The connection is clear and intentional.