What does AD mean?

Below I have reposted a devotional I receive by email. It seems fitting this first day of 2015.  I am going to do something new. It is already happening. Don’t you recognize it? I will clear a way in the desert. I will make rivers on dry land. (Isaiah 43:19 GW)

Today is the first day of 2015 AD. 2015 BC means 2015 years before Christ's birth. 2015 AD means 2015 years after Christ's birth.  AD is Medieval Latin for Anno Domini which means "In the year of our Lord Jesus Christ." It is interesting that the birth of Jesus Christ divided our calendar, so that nearly the whole world marks time according to the time of Jesus' entrance. Government documents still use this Christian phrase. President Obama ended his proclamation for National Park Week with: "I have hereunto set my hand this sixteenth day of April, in the year of our Lord two thousand ten..." It is fitting that Jesus Christ is the separation of the "old" and the "new." The birth, life, ministry, death, and resurrection of Christ are the "turning points" in world history. It is also true when He comes into our individual lives. "If anyone is in Christ, he is a new creation; the old has gone, the new has come" (2 Corinthians 5:17). I know AD has a Latin meaning, but I like to think of AD as meaning "After Divinity entered the world. He is now "God with us." Dear Jesus, Your coming into my world has changed everything for me! "At the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the glory of God the Father" (Philippians 2:10-11).