At that time Jesus was going through a field of grain on the sabbath. His disciples were hungry and began to pick the heads of grain and eat them. When the Pharisees saw this, they said to him, "See, your disciples are doing what is unlawful to do on the sabbath." He said to them, "Have you not read what David did when he and his companions were hungry, how he went into the house of God and ate the bread of offering, which neither he nor his companions but only the priests could lawfully eat? Or have you not read in the law that on the sabbath the priests serving in the temple violate the sabbath and are innocent? I say to you, something greater than the temple is here. If you knew what this meant, 'I desire mercy, not sacrifice,' you would not have condemned these innocent men. For the Son of Man is Lord of the sabbath." (Mt 12:1-8)
The disciples were hungry. The natural and human need for food makes them forget the rules. Hunger makes them forget even holy things like sabbath. Basic human needs and wants make one to forget everything. When one faces the question of survival then all the reasoning disappears.
The Pharisees were worried about the rules only. For them everything was linked to following the rules. Nothing existed without the rules. Not only that, but also that the rules prevailed above everything else. Rules were for them the primary thing. Primacy of rules ruled their lives. Following of the rules will make them neglect even a dying neighbour (Story of the Good Samaritan)
Jesus, in stead, is different from the above two types of people. Basic human needs were not his primary concern. Rules of the society or religion were not his primary concern. For Jesus, humanity was his main, primary concern. For Jesus, the person (image and likeness of God) is more important than anything and everything.
