The Fulfillment of a Prophecy
"pairing an event of Edward's career with its biblical precedent "
This part of the parchment is an allegorical representation of Edward's fulfilment of a prophecy witnessed the day before the battle.
Shortly after the battle Edward heard of the capture of Owen Tudor, he called on his Welsh ally Roger Vaughan and ordered him to Usk Castle, where it is said Tudor was held captive. Owen Tudor was summarily executed, beheaded in Hereford market square, it was Roger Vaughan who swung the axe. Edward was a king in the making, for now, there would be those whose indiscretions he could tolerate but not when it came to avenging the deaths of those he held dear, and Edward struck, just like John Clifford had at Wakefield.
Three Fifteenth Century Chronicles, with Historical Memoranda - John Stow