Psalm 81:10 (NASB)
Open your mouth wide and I will fill it.
There's much speculation about how the Lord sustained Himself for forty days and nights without any food or water in the desert (Matthew 4:2). Some say that it was just a narrative, not literally forty days and nights. Some say He lived off the desert like John the Baptist, who ate locusts and wild honey (Matthew 3:4). I'm inclined to believe that the Holy Spirit sustained him. The same power of God that created this universe with merely His spoken word (Genesis 3:1-26) also sustained life in Him for that duration. The indwelling power of the Holy Spirit that brought the Apostle Paul back to life when everyone left him for dead (Acts 14:9) sustained life in Christ during that period of fasting and starvation. The power of God that neutralized the rattle snake's venom and left Paul alive (Acts 28:3-5) also sustained Christ in the desert.
So the next time you sit for a lavish dinner and the Holy Spirit whispers to you, "man does not live on bread alone" (Matthew 4:4), don't brush Him aside but believe Him to be true