Mark presents to us a fast moving Jesus, one who is always in action: healing, teaching, eating, traveling, stuff like that. It's important to remember that Jesus is portrayed as a rabbi, which is a Jewish instructor of the Torah. A rabbi would pick about twelve men, who would then live with him, travel with him, learn from him the meaning of the Torah. The exepectation for these disciples would be that they then might become a rabbi, able to teach the Torah, and live by the Torah. They gained recognition and respect for their ability to both live by the Torah and explain the Torah. This is what we see Jesus doing as a rabbi, and often he is correcting the powerful Pharisees, who prided themselves on being able to live by and explain the Torah.
In chapter seven, Mark retells a story of Jesus the rabbi confronting the picky Pharisees; actually Jesus doesn't start it, but he knows how to finish it! They pick on him and his disciples for not living ceremonially clean (a common expectation for rabbis and rabbi disciples). Jesus cuts right to the heart: why complain about dirty hands when you dishonor your folks.
Jesus points out their duplicity: in an effort to not spend their resources on their aging parents, and in an effort to appear pious by spending extra amounts of money on almsgiving and proselytizing, they neglected their parents in their great time of need. What did it mean to "honor your father and mother"? It meant to care for them as they age and grow increasingly dependent. It means to care for them at your own expense. Even if this means you can't devote as much "money" or resources to God as you would like. They were supposed to set aside money for God and their parents. Instead they ditched their folks and "devoted" their money to God, which ended up dishonoring them and God.
Should a missionary go overseas if his parents need him to stay in town to drive them to their doctor appointments?
Should a pastor turn down an attractive ministry position if taking it meant leaving his parents alone and isolated?
Should a Christian businessman take the promotion if it means moving far enough away such that his parents are left feeling helpless when it comes to handling their medical and insurance bills?
Should a Christian family move away from their aging and dependent parents because of personal dreams and ambitions?
What does Jesus mean by "honoring your father and mother" in our day?