"The most important thing about a person is what that person thinks when they think about God." A.W. Tozer
We often speak of the God of the Old Testament and the God of the New Testament, as if to say that they are separate beings. In our minds we juggle the concepts as they battle each other. We struggle to blend the image that the Old Testament portrays with the image portrayed in the New Testament - Holy and Just with a dash of jealous and vengeful vs. a loving Father who made the greatest sacrifice to save us. Who wins?
I know I tend to lean towards the Old Testament God when things are going well, figuring he's going to "get me" soon, like some sort of supernatural boogey man, and something bad will happen; I hope for the New Testament God when times are tougher, that he would come love on me.
But really - there's only one God! The 1001 rules God is the love and grace God. It almost doesn't make sense, but the thing of it is, it's true. There is only one God and He's never changed.
Now hold on just a second! How can that work? How can He be the one God and be the same "yesterday, today, and tomorrow?"
The answer lies in the fact that God does not exist in a vacuum: He created us so He could love someone - not something, like I love warm socks, but someone. And by loving someone he's created a relationship, and relationships are dynamic.
God is our father, and like a father's love must take different forms as a child grows and matures, God's dealings with us have changed as we grew more mature, and in order to cause us to mature.
With a toddler, you spend your every waking hour (it would seem) saying "No." I think of the 10 commandments and some of the subsequent laws as a long list of No's. As the child gets a little older they start applying this - imposing their own No's on others, even their parents. Hence the Pharisees and the Saducees and all the regulations added in our attempt to use what we thought was the right way to live.
But at some point a parent needs to break that cycle and show the child grace and a little trust, both because the child is maturing and ready to understand and to push the child to further mature. This is where we are in the New Testament and beyond - God is now the father of a teenager/young adult - we screw up a lot, but we're beyond the spanking stage. Now he must love us until we learn the ways of that love.
It's not God who has changed, it's us. But we're still in that teenager/young adult stage - we're conflicted and we only accept things in parts. We still try to impose regulations where we shouldn't; we go too far in love sometimes and allow ourselves to do things we shouldn't. We get angry and sullen when we're frustrated. We try to do damage to ourselves. We try to fix some of our problems on our own, so we won't have to own up to them. We're on the cusp of beginning maturity, we're complicated, and we're loved.
And we think that we are the only constant in the equation, but we are constantly changing - He's always been the same.