…which only God Himself can fill.

This famous phrase, reportedly coined by Blaise Pascal (philosopher, scientist & author), referring to “the God-shaped vacuum” in everyone, may actually be (according to Dr Douglas Groothuis), a paraphrase from one of Pascal’s Pensées —

What else does this craving, and this helplessness, proclaim but that there was once in man a true happiness, of which all that now remains is the empty print and trace? This he tries in vain to fill with everything around him, seeking in things that are not there the help he cannot find in those that are, though none can help, since this infinite abyss can be filled only with an infinite and immutable object; in other words by God himself.
(Penguin ed., 148/428).

pdb