Exodus 34:28 NKJV
So he was there with the Lord forty days and forty nights; he neither ate bread nor drank water. And He wrote on the tablets the words of the covenant, the Ten Commandments.
Moses was in the glory of God for 40 days. His physical body was sustained without natural food or water.
Spiritual significance: The spirit world is more real than the natural world. Everything in our natural world came from the Spirit world. Our spirits will exist without our bodies, but our bodies cannot live without our spirits. Although we need natural water for physical bodies, spiritual water provides more benefit. The power of the water of the Word and the water of the Spirit should not be underestimated. Jesus spoke to the Samaritan woman of the superiority of spiritual water. He also told the Jews about spiritual water.
John 4:13-14 NKJV: Jesus answered and said to her, "Whoever drinks of this water will thirst again, but whoever drinks of the water that I shall give him will never thirst. But the water that I shall give him will become in him a fountain of water springing up into everlasting life."
John 7:37-39 NKJV: On the last day, that great day of the feast, Jesus stood and cried out, saying, “If anyone thirsts, let him come to Me and drink. He who believes in Me, as the Scripture has said, out of his heart will flow rivers of living water.” But this He spoke concerning the Spirit, whom those believing in Him would receive; for the Holy Spirit was not yet given, because Jesus was not yet glorified.
We cannot experience what Moses experienced in terms of being able to go such a long time without food or water unless God chose to give us such a divine encounter. However, we can learn from Moses' experience and benefit if we take the lesson that spending time in God's presence reaps benefits for our whole being – spirit, soul and body.