I agree. Give him time. It's actually a huge step from atheism to theism, and at age 81 he's got to fight against the very well worn ruts in his way of thinking. Even C.S. Lewis didn't move directly from atheism to Christianity. He first became a theist, with a vague belief in some sort of God, then a Christian.
I heard someone say today,,,
I am not where I want to be, I am not where I ought to be, I am not where I am going to be, but thank God, I'm not where I used to be.
Very appropriate timing I would say.