In every age and in every movement of God's people, it seems that the biggest struggle we have always faced was the problem of "majoring in minors." It is so incredibly easy to get off track and find ourselves pursuing good minor pursuits at the exclusion of the important and major ones.
Jesus does not criticize the religious leaders of his day for taking scrupulous care of God's laws. What really irritates him and brings his condemnation upon them is that as they took minute care with small matters, they also completely abandoned the key matters, the core issues. You see, discipleship has always been about character and concern: reflecting the character of our Lord and being concerned about the same things that concern him. Unfortunately, we find it easy to fight over these gnat issues and swallow the camel issues. Jesus reminds us what is central: justice, mercy, and faithfulness!