Treachery implies some sort of betrayal or deceit on our part. We clearly warned Oman not to return to our borders. If you were defending Tamya, why not move your army next to the town, preventing any attack?

The army in question had already departed Ayyubid lands, but then reveresed course, bypassed the town it was "protecting" and encamped itself on the border of their ally's enemy. To us, this army had no reason for being there but to militarily engage the Kingdom in defence of the Ayyubids. This constituted a clear threat to the Kingdom, so the threat was elminated.