For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled. Matt. 5:18.
Jesus couldn't have said it stronger. Nothing can ever change God's law in the slightest degree. Its demands are permanent.
Just as heaven and earth are signs of stability in the sense that they are always there, so is God's law unending. It is not something that He alters from time to time because He might feel the urge to do something different. No, its principles are built into the very fabric of the universe.
I like the way The Message renders the first part of our verse: "God's law is more real and lasting than the stars in the sky and the ground at your feet. Long after the stars burn out and earth wears out, God's law will be alive and working."
Now, that is permanent!
But why? Doesn't God have a free will? Can't He choose to do what He wants?
Of course He can do as He pleases. But the questions miss the point. The way of God's basic law is the way of health and life. Anything contrary to the law is death, destruction, and disorder. Take the Ten Commandments, for example. You can't have a healthy society in which people are killing one another and in which you can never trust anyone.
God's law cannot be changed because it is an outward representation of His character of love. Its very principles are for our eternal good.
Thus not even the smallest part of God's law--not a "jot or a tittle" (the smallest letter and the smallest point in the Hebrew alphabet)--will be altered. It is for our good.
And while that is true for the Ten Commandments, it is also the case of the entire Old Testament--the law and the prophets. The Old Testament still has validity for Christians.
Even the ceremonial law has meaning for us. What was nailed to the cross was the penalty for breaking the law rather than any part of the law itself. The ceremonial law is being fulfilled in the ministry of Christ. He was the Lamb who died for us (John 1:29), He is our Passover (1 Cor. 5:7), and He is currently functioning in the heavenly sanctuary as our great High Priest, as described extensively in the book of Hebrews. The action of the ceremonial law has shifted from earth to heaven, where the loving Christ is interceding for me today.