[Of all the answers in the Catechism, this may be my personal favourite, other than the famous first and last ones. It presents as attractive a definition of providence as you will find anywhere, and does it in a way that makes Reformed theology look both thoroughly practical and thoroughly beautiful (which, let's face it, is not always the case). God is my creator and my Father, he provides whatever I need, and he will always turn anything bad into good, being both able (as Almighty God) and desiring (as faithful Father) to do so.

As an aside, it is worth noting that Heidelberg presents God as a sender of adversity, which I have commented on here before, but also that this is intimately connected with his ability to turn it to our good. A God who can send the storms can also say "thus far, and no farther" (Job 38:11); a God who can ordain the betrayal and death of his Son (Acts 4:28) can also ensure that it works to save all who believe. If God is not sovereign over Satan himself, such that everything that happens ultimately sits under his authority, then we cannot be certain that all things will work out for our good. But he is, and it does, so we can.]