"and they shall not escape.” But he adds, to those who have given heed to the Saviour's warning: “Ye, brethren, are not in darkness, that that day should overtake you as a thief. Ye are all the children of light, and the children of the day: we are not of the night, nor of darkness.” 1 Thessalonians 5:2-5 . GC 371.1"
"For yourselves know perfectly that the day of the Lord so cometh as a thief in the night. For when they shall say, Peace and safety; then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape. But ye, brethren, are not in darkness, that that day should overtake you as a thief. Ye are all the children of light, and the children of the day: we are not of the night, nor of darkness."
Ellen White directly references 1 Thessalonians 5:2-5 in this passage.