1 God’s saving of man is not done directly through the means of the Spirit or as the Spirit, for His Spirit can neither be touched nor seen by man, and cannot be approached by man. If He tried to save man directly in the manner of the Spirit, man would be unable to receive His salvation. And if not for God putting on the outward form of a created man, they would be unable to receive this salvation. For man can in no way approach Him, much like how none could go near the cloud of Jehovah. Only by becoming a man of creation, that is, putting His word into the flesh He will become, can He personally work the word into all who follow Him. Only then can man hear for himself His word, see His word, and receive His word, then through this be fully saved. If God did not become flesh, no fleshly man would receive such great salvation, nor would a single man be saved. If the Spirit of God worked directly among man, man would be smitten or completely carried away captive by Satan because man is unable to associate with God.
from “The Mystery of the Incarnation (4)” in The Word Appears in the Flesh