"Moses had much to communicate to them; and compassionating their fear, he put a veil upon his face, and continued to do so thereafter whenever he returned to the camp from communion with God. PP 330.1"
"And till Moses had done speaking with them, he put a vail on his face."
The EGW passage directly refers to and explains the reason behind Moses veiling his face, as mentioned in Exodus 34:33.
"By this brightness God designed to impress upon Israel the sacred, exalted character of His law, and the glory of the gospel revealed through Christ. While Moses was in the mount, God presented to him, not only the tables of the law, but also the plan of salvation. He saw that the sacrifice of Christ was prefigured by all the types and symbols of the Jewish age; and it was the heavenly light streaming from Calvary, no less than the glory of the law of God, that shed such a radiance upon the face of Moses. That divine illumination symbolized the glory of the dispensation of which Moses was the visible mediator, a representative of the one true Intercessor. PP 330.2"
"And it came to pass, when Moses came down from mount Sinai with the two tables of testimony in Moses’ hand, when he came down from the mount, that Moses wist not that the skin of his face shone while he talked with him."
EGW connects the shining face of Moses in Exodus 34:29 with the glory of God's law and the gospel revealed through Christ. While not a direct quote, it's a clear interpretation and expansion of the biblical narrative.
"The glory reflected in the countenance of Moses illustrates the blessings to be received by God's commandment-keeping people through the mediation of Christ. It testifies that the closer our communion with God, and the clearer our knowledge of His requirements, the more fully shall we be conformed to the divine image, and the more readily do we become partakers of the divine nature. PP 330.3"
"But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord."
EGW draws a parallel between the shining face of Moses and the transformation of believers into the image of Christ, echoing the sentiment expressed in 2 Corinthians 3:18 about beholding the glory of the Lord and being changed into His image.