God works in mysterious ways. Here, through dramatic street-theatre, we learn of the split of the united kingdom of Israel, and Jeroboam learns of his pending kingship of the ten separated tribes. Rather than have Ahijah just speak the prophecy in words, it was necessary to physicalise it in some way, to illustrate the tearing apart of the nation through the tearing apart of a new garment. Twice we are told the garment is new, giving this aspect some significance. Israel itself was still new, never had a chance to really do what it was intended to do: lay the foundation for all civilisation for a new way of living, and now, before its time, torn apart.

Ahijah's symbolic action is one of many examples of similar 'performances', known as sign acts or prophetic gestures.¹ There are many examples in the books of the prophets, e.g. Jeremiah smashing pottery,² Ezekiel baking bread over human waste,³ and Isaiah going naked for three years.⁴ Such acts may seem strange to us, or even superfluous, but when we consider our own teaching methods over the centuries, we must admit that the common practice of telling people things has little impact—lecture is the least useful way of teaching. It is experiential learning that takes hold. This is why good educators today use visual aids, props, video and even theatre experiences to help students embody new ideas, rather than just 'know' them. Learning must be a multi-dimensional experience, and the old testament prophets knew this several thousand years before we rediscovered it in the 20th century.

¹ A full list of such gestures can be found here: Theatrical Prophetic Sign Acts in the Bible. I also recommend The Weird, Wonderful World of Prophetic Communication by W. Woollard, 2019
² Jeremiah 19
³ Ezekiel 4:12
⁴ Isaiah 20:1-4