John Chrysostom — as excerpted in the Catena Aurea on John 6:1-14

“(Hom. xlii. 2.) But why when He is going to heal the impotent, to raise the dead, to calm the sea, does He not pray, but here does give thanks? To teach us to give thanks to God, whenever we sit down to eat. And He prays more in lesser matters, in order to shew that He does not pray from any motive of need. For had prayer been really necessary to supply His wants, His praying would have been in proportion to the importance of each particular work. But acting, as He does, on His own authority, it is evident, He only prays out of condescension to us. And, as a great multitude was collected, it was an opportunity of impressing on them, that His coming was in accordance with God’s will. Accordingly, when a miracle was private, He did not pray; when numbers were present, He did.”