Jesus fasts first. He wants to be lean and prepared and alert and hungry. Jesus is facing his identity. The temptations are all about how he is who he is. Jesus is confronting temptations to use his personal power for himself, rather than for others.
Freedom is all about confronting the temptation to use one's power to feed oneself.
The demon is always to focus on our hungers and to fear we will starve. Self absorption always defeats our ability to freely give ourselves for others. The gospels tell us Jesus knew this temptation. He learned to depend upon God's word for his nourishment. Then he was free to be broken and given as food for us all.