Jesus answered, “It is written: ‘Man shall not live on bread alone, but on every word that comes from the mouth of God.'” Matthew 4:4.
If God so willed it we could live without bread, even as Jesus did for forty days; but we could not live without His Word. By that Word we were created, and by it alone can we be kept in being, for he sustaineth all things by the Word of His power. Bread is a second cause; the Lord Himself is the first source of our sustenance. He can work without the second cause as well as with it; and we must not tie Him down to one mode of operation. Let us not be too eager after the visible, but let us look to the invisible God. We have heard believers say that in deep poverty, when bread ran short, their appetites became short, too; and to others, when common supplies failed, the Lord has sent in unexpected help.
But we must have the Word of the Lord. With this alone we can withstand the devil. Take this from us, and our enemy will have us in his power, for we shall soon faint. Our souls need food, and there is none for them outside of the Word of the Lord. All the books and all the preachers in the world cannot furnish us a single meal: it is only the Word from the mouth of God that can fill the mouth of a believer. Lord, evermore give us this bread. We prize it above royal dainties.
Charles H Spurgeon