Luke 4:3-4 NKJV
And the devil said to Him, “If You are the Son of God, command this stone to become bread.”
 But Jesus answered him, saying, “It is written, ‘Man shall not live by bread alone, but by every word of God.'”
Deuteronomy 8:2-3 NKJV
And you shall remember that the LORD your God led you all the way these forty years in the wilderness, to humble you and test you, to know what was in your heart, whether you would keep His commandments or not.
 So He humbled you, allowed you to hunger, and fed you with manna which you did not know nor did your fathers know, that He might make you know that man shall not live by bread alone; but man lives by every word that proceeds from the mouth of the LORD.
God made Israel passed through the wilderness feeding them with one type of food for forty years. He GAVE them no other choice of food but one, the Manna. And He had one reason for doing that, JUST TO TEST THEIR HEART AND TO KNOW IF THEY WOULD OBEY HIM OR NOT.
it was a grievous test to the whole people of Israel, that He might let them know that “Man shall not live by bread alone, but by every Word that proceeds from the mouth of God. God wanted the people to learn to chose His Words above their personal desire, above food, above self gratification, above their personal ambition and desires. He wanted them to know that what matters is “Whatever the Lord says over a situation and over an issue matters over other things.”
He had the power to give the people of Israel all manner of food and drinks in the wilderness, but what matters to God most was their attitude of obedience to His command, and purpose for them.
God put the first Couple in the beautiful Garden of Eden. He provided therein for them all what tbey could need. But He placed the Forbidden Tree in the midst of the Garden, and commanded them not to touch it. Therefore, what mattered to God above all He provided for the couple in the Garden was their attitude to obeying His Voice, His command, His instructions. So even in the garden of Eden, He expected Adam and Eve to live by His Word alone, obeying every of His instructions, and not only by the food that was abundant everywhere in the garden.
Genesis 3:4-6 NKJV
Then the serpent said to the woman, “You will not surely die.
 For God knows that in the day you eat of it your eyes will be opened, and you will be like God, knowing good and evil.”
 So when the woman saw that the tree was good for food, that it was pleasant to the eyes, and a tree desirable to make one wise, she took of its fruit and ate. She also gave to her husband with her, and he ate.
Thus, in the Garden, Eve and Adam chose Enlightenment and Acquisition of human wisdom above the express Instructions of God, so, they chose to eat what the Lord told them not to eat in order to have more wisdom and knowledge and be like God.
Therefore, “Living By Bread alone above the Word of God ” stands for choosing to do things differently from the mind of God.
Elisha had refused the gifts brought by .Naman, but Gehazi did not see anything bad in collecting the gift. So HE went for it against the will of his master and lost all his ministerial Heritage and secured a Legacy of leprosy for himself and his generations. He chose to live by the bread alone.
Judas, who was a part of the disciples of Jesus Christ, and was to be glorified with the rest of these disciples in eternity, but he chose to collect a meagre 30 pieces of silver and betrayed his Master rather that staying by his Lord and ruling with Him in eternity. He chose to live by bread alone.
When you desire to please yourself in whatever way rather than listening to and obeying the Word of God, you are ” living by the Bread alone”. When, Samson, a Nazarite dedicated and anointed from the womb to save the land of Israel, chose to pitch his tent with the ladies of the Philistines and married out of them, a lady who would sell him off, he had chosen to “live by the bread alone” above the Word of God.
When you chose to live with your worldly friends because of the pleasures and the ungodly benefits you derives from them, you are choosing to live by the Bread alone.
Whenever you are confronted with the option of either to do the will of God or to tend to your own captivating, seductive, tempting, seemingly profitable ways, you are being offered to Live by the Bread alone above the Word that proceeded from the Mouth of the Lord.
John 6:49, 51 NKJV
 Your fathers ate the manna in the wilderness, and are dead.
 I am the living bread which came down from heaven. If anyone eats of this bread, he will live forever; and the bread that I shall give is My flesh, which I shall give for the life of the world.”
“Living by the Bread alone” is doing your personal wills, living to fulfill your passion and ambitions alone, fulfilling your personal dreams and aspirations without considering the mind and Plans of God for your life. Living that way will eventually lead to dead end, no profitable destination in life. Adam and Eve fell for it and were checked out of the Garden and entered into a world of sweat and labor.
ANYTIME THE TEMPTATIONS COME TO ACT AGAINST THE WORD OF GOD, IT IS THE DEVIL PRESENTING THE BREAD ABOVE THE WORD OF GOD.
May I never sacrifice the Will and Plan of God for my own personal Ambition and selfish desire.