Chapter 5.2, 5.3
ii. Although, in relation to the foreknowledge and decree of God, the first Cause, all things come to pass immutably, and infallibly; yet, by the same providence, He ordereth them to fall out, according to the nature of second causes, either necessarily, freely, or contingently.
iii. God, in His ordinary providence, maketh use of means, yet is free to work without, above, and against them, at His pleasure.
Once it is established that all things come to pass under God's wise governance, it remains to consider the ways in which his providence operates, as well as the implications this doctrine has for the freedom of human action.
Section two repeats an important biblical word from section one--the word "foreknowledge" (e.g. Acts 2:23; Romans 8:29). The doctrine of providence concerns what God knows (and knows in advance) as well as what God does. He is not making things up as he goes along, but working his eternal plan. Whatever happens is something he knew would happen before it happens.
That is not all. Divine knowledge of coming events is more than a supernatural power to predict the future. God knows what will happen because he decrees it to happen. For him to foreknow is to foreordain.
This does not mean that God forces people to do things against their will, or that everything in the universe is moved by some immediate exercise of his divine power. Instead, God typically works out his purposes through human decisions, natural laws, and the many causes and reactions that are constantly at play in ordinary life--what the Westminster Confession refers to as "second causes."
A "second cause" is simply "a cause caused by something else." This expression is used in theology to distinguish between God as the ultimate cause of everything that comes to pass and the myriad smaller causes we see at work in the world.
Some of these second causes are as necessary as the laws of physics. Others are as free as the decision to order a cheeseburger. But whether things happen by necessity or contingency, they all occur under the overarching providence of God. Even chance and probability are the servants of his will.
The third section opens up space for divine miracles. God typically works through the ordinary means of providence, such as the harvest time that comes in autumn, or the daily care that a mother gives her baby. Yet even the laws of nature do not constrain the power of God, who has the freedom to turn water into wine, give sight to the blind, and bring the dead back to life.