Honor your father and your mother ... that your days may be long upon the land which The Lord your God is giving you.
This is the most important commandment after the first four commandments of how we must only worship God.
God commands us to show our parents utter respect, because they stand in for Him ... to raise us as children of God.
If it weren't for our parents, we wouldn't have been alive. They raised, took care and nurtured us to adulthood ... always there when we needed them.
It is our duty to repay our parents in kind when they grow old and feeble. We then must take care of them.
FINISH
Source: The Bible: Exodus 20