Here's a possible model. God transcends time and space. He is not part of our universe but can enter into it at will. Here's an analogy. From my dining room window, I can see a clothesline hanging in my backyard. Imagine that clothesline as time. I can see the whole thing at once. I can zoom in with a microscope and see the tiniest part of it. This is how God is related to our universe. Now imagine a flea walking on the line. (To make this work, imagine that the flea keeps walking in one direction and can't turn around.) To the flea, he sees just an inch ahead of him. Beyond that is non-existence (the future). If he looks behind him, he can only see an inch, beyond which is oblivion (the past). He exists at the point where oblivion meets non-existence. What's the point of it all? But I can see the flea. I can see clearly where he was. I can also see that in five minutes, he's going to come across a drop of honey I put on the clothesline for him. All of the flea's experiences are Now to me. My knowledge of the flea's past, present and future does not detract from the flea's freedom. In five minutes, the flea will be eating honey, as I determined. He will be doing it of his own free will.