Jesus answered, “It is written: ‘Man shall not live on bread alone, but on every word that comes from the mouth of God.’”
Man SHALL not live on bread alone for you may eat all the bread you like but you will still eventually die so you SHALL not live. The only way to LIVE is to eat the word of God, that is, to read it and believe it and believing it obey it – and then you SHALL live, first, more fully and satisfyingly here on earth and then more joyfully beyond anything you can imagine for ETERNITY. I do not believe the translation here clearly conveys the whole meaning, it should read, “Man shall not live (eternally or fully here on earth) on bread alone, but (ONLY by believing ) every word that comes from the mouth of God.”
Lets think about the entire episode here for a minute. Jesus has been fasting for forty day, nothing but water, nothing to eat for a month and 10 days, do you think He was weak and hungry? Well, we know He was because it says, “After fasting forty days and forty nights, he was hungry”. And then what happens that causes Him to say this, “The tempter came to him and said, ‘If you are the Son of God, tell these stones to become bread’.” Now, you or I, possessing Jesus’s ability would have turned some stones into bread long before 40 days and do not believe the tempter just showed up after 40 days, he was there all along tempting, tempting, tempting Jesus just he does us every day. We know this also because the text tells us, “Then Jesus was led by the Spirit into the wilderness to be tempted by the devil.” Now, here is the thing, Jesus did not resist the temptation because of His deity, while He was fasting He was a man just like you and me, He resisted temptation because He was obedient to God. Much more so than you or I Jesus had the power to do something about His hunger and yet He still resisted the temptation – think about that next time you are about to give in to any temptation, think about how weak you are in your flesh and how strong Jesus was in His and realize that is the reason you need His perfect obedience, His righteousness because if anything should become obvious it is how your righteousness is nothing but filthy rags.