Nullus constabularius distringat aliquem militem ad dandum denarios pro custodia castri si facere voluerit custodiam illam in propria persona sua vel per alium probum hominem, si ipse eam facere non possit propter racionabilem causam et si nos duxerimus vel miserimus eum in exercitum, erit quietus de custodia, secundum quantitatem temporis quo per nos fuerit in exercitu.
No constable may compel a knight to pay money for castle-guard if the knight is willing to undertake the guard in person, or with reasonable excuse to supply some other fit man to do it. A knight taken or sent on military service shall be excused from castle-guard for the period of this service.