Galatians 4:4 states that “when the fullness of time had come, God sent forth His Son, born of a woman, born under the law.” But what does “fullness of time” mean? I have always been fascinated with time, wrestling with its metaphysics. Augustine admitted that he could not explain what time is. Time is a great mystery even to modern-day physicists.

Newton believed in absolute time (“God time”) that is the same everywhere for everyone in the Universe. But Einstein proved that time is relative to velocity; the faster one moves the slower time progresses for them. If true, what does Galatians 4:4 refer to then when it uses the phrase “fullness of time?”

Today I was reading Tatian’s 2nd century apology to the Greeks. In it, he discusses time and uses the analogy of a ship sailing along a coastline. From the perspective of a passenger on the ship, the hills on the shore appear to be moving – but in fact, the ship itself is moving creating the illusion. Similarly, Tatian argues that time is fixed and that we move through time, creating the illusion that time is passing. If this perspective is correct then time does not flow past us but we move through time which is fixed. Just as the speed of the ship will affect how fast the hills move, so our velocity in the Universe changes how fast time moves past us (Einstein was correct).

If this is a correct understanding then the “fullness of time” refers to when the world reaches a predetermined state, not to some arbitrary measurement of passing time. By way of analogy, it is when the ship reaches the destination port. In other words, when the world with its fallen image-bearers reached a predetermined condition of affairs, God sent his Son.

After my current book is finished – God willing – I hope to write a book exploring the theological understanding of time, grappling with its mysterious metaphysics.