The terms imply periods of time referring to life before and after the birth of the very important Son of God. Whether one recognizes this man as a prophet, rabbi, or King, this man had a significant impact on society even to this day.
I have a similar use for the term "b.c". I sometimes casually use the term to mean my life "before children". Before I had my own children, I did not really know how much goes into loving another person. Parental love (not necessarily biological) is something very special. It is self sacrificing and most rewarding. So is the love many teachers have for the children under their care. Some teachers have literally given their lives to protect children.
I have a similar use for the term "b.c". I sometimes casually use the term to mean my life "before children". Before I had my own children, I did not really know how much goes into loving another person. Parental love (not necessarily biological) is something very special. It is self sacrificing and most rewarding. So is the love many teachers have for the children under their care. Some teachers have literally given their lives to protect children.