The concept of obedience comes from the religious traditions in almost every culture. It was only natural for people to obey Gods' Will when they believed to be completely dependent on them.
It also created fundaments for many societies and simple social relations, like those between parents and children. Just as a good obedient believer would be rewarded for their prayers, an obedient child would be praised by their parents.
And so it went... is it true then, that child's love shows through obedience to their parents? Just as a God is wiser than people, parents, through their experience, know life better than children and so deserve respect. Being obedient is also a way to show that respect.