Predestination and free will

I had an interesting discussion with a colleague about predestination and free will. I told her that it was a weighty topic and I did not know enough about it. We threw up a few things and following that, I decided to google it and came upon this Spurgeon extract, which, to me, was a pretty good explanation of the two truths. I've not studied the subject enough or read the bible thoroughly enough to get a grip on these two truths but I thought Spurgeon's comments hit the nail on the spot.

C.H.Spurgeon:

The system of truth is not one straight line, but two. No man will ever get a right view of the gospel until he knows how to look at the two lines at once.

I am taught in one book to believe that what I sow I shall reap: I am taught in another place, that "it is not of him that willeth nor of him that runneth, but of God that showeth mercy."

I see in one place, God presiding over all in providence; and yet I see, and I cannot help seeing, that man acts as he pleases, and that God has left his actions to his own will, in a great measure.

Now, if I were to declare that man was so free to act, that there was no presidence of God over his actions, I should be driven very near to Atheism; and if, on the other hand, I declare that God so overrules all things, as that man is not free enough to be responsible, I am driven at once into Antinomianism or fatalism.

That God predestines, and that man is responsible, are two things that few can see. They are believed to be inconsistent and contradictory; but they are not. It is just the fault of our weak judgment. Two truths cannot be contradictory to each other.

If, then, I find taught in one place that everything is fore-ordained, that is true; and if I find in another place that man is responsible for all his actions, that is true; and it is my folly that leads me to imagine that two truths can ever contradict each other.

These two truths, I do not believe, can ever be welded into one upon any human anvil, but one they shall be in eternity: they are two lines that are so nearly parallel, that the mind that shall pursue them farthest, will never discover that they converge; but they do converge, and they will meet somewhere in eternity, close to the throne of God, whence all truth doth spring.