"Everything that has a beginning has an end."
That's a quote from a line in "The Matrix Revolutions", and it's true - but not about God.
Revelation 22:13 tells us "I am the Alpha and the Omega, the First and the Last, the Beginning and the End." I don't think its interesting or coincidental that this verse is in the last chapter of God's word. In this same chapter he tells us he is "coming soon" - he uses this time (through John) to reassure us that he has been wherever we are going and not to worry about His return because whenever it is he's already been there.
God has no ending because He had no beginning He has always been and He will always be. Any beginnings He refers to in His word is in relation to our beginning - not His.
There is no ending for God, because there was no beginning.