We must live a twofold life—a life of thought and action, of silent prayer and earnest work. All who have received the light of truth should feel it their duty to shed rays of light upon the pathway of the impenitent. They should be witnesses for Christ in our offices as verily as in the church. God requires us to be living epistles, known and read of all men. The soul that turns to God for its strength, its support, its power, by daily, earnest prayer, will have noble aspirations, clear perceptions of truth and duty, lofty purposes of action, and a continual hungering and thirsting after righteousness. By maintaining a connection with God we shall be enabled to diffuse to others, through our association with them, the light, the peace, the serenity, that rules in our hearts, and set before them an example of unwavering fidelity to the interests of the work in which we are engaged. 4T 459.3 With many who are laboring in our offices there is an almost entire absence of the love and fear…
"Ye are our epistle written in our hearts, known and read of all men: Forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart."
EGW directly uses the phrase 'living epistles, known and read of all men,' which is a clear and direct reference to 2 Corinthians 3:2-3.
"Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven."
Both passages discuss the idea of believers being a light to others. EGW's passage expands on this by describing how maintaining a connection with God allows believers to diffuse light and peace to those around them, reflecting the principle of letting one's light shine.