Fast flowing water is a protection. Crossing a stream can keep the fugitive safe

Evil stops at the edge of the water. Purity rejects the corrupted spirit. Demons can't cross it, dragons avoid it.

Fleeing for safety, running for the next world; the horses' hooves carve holes in the turf.

Crossing a river can be a new beginning. Paying the ferry man can also provide transport to Hell.

Don't forget the demons in the water. They lie hidden and will rise up to gut the runners as they pass.

Don't look back. Keep going. Something might be gaining on you.