Several times in the Greek text, the Greek word for “Lord” should be translated “despot”; it's one who would exact his pound of flesh; justice is justice and right is right. He said unto his disciples one day, “why call ye me Lord, Lord, and do not the things that I say?” A lord is one who has control; he has authority and is one before whom we prostrate ourselves and humbly submit ourselves to his will in obedience to his commandments.
If we are willfully disobedient, we deny this; we're saying, "I'm going to do what I want instead of what you want". It's saying that he's not Lord, for at least that moment.
Now, to use the "father" analogy, your father is your father, no matter what. You are born and cannot be unborn. But, if you work, your boss will not always be your boss.
The instant that you're saved, you're born from above and you're in the family. You cannot be unborn.
But, that doesn't mean that you will always submit yourself to his will in obedience to his commandments.
Edited to add: Before someone jumps on me for calling the Lord a "despot", I wanted to past the definition here. Today, in modern English, "despot" is often synonymous with "tyrant". But, that's not the primary definition of the word.
des•pot \"des-pet, -'pat\ n [MF despote, fr. Gk despotes master, lord, autocrat] 1 : a ruler with absolute power and authority 2 : a person exercising power tyrannically — des•pot•ic \des-"pa-tik\ adj — des•po•tism \"des-pe-'ti-zem\ n
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