There is evidence that the incomplete church was used for stabling horses during the siege. However, it seems that some parts were used for worship. A wedding is recorded on 10 May 1644, baptisms from January 1645 and burials from 4 August 1646 (some pages have been lost so there may have been earlier ones). The oldest communion plate is hallmarked 1646 suggesting its early use. Although the church was not consecrated until 2 September 1665, Francis Porter the first minister was in place as the preaching minister at Charles from 1643 as allowed for by the Act. Iron spikes were said to have been driven into the chancel wall and a canvas pulled across part of the church making it useful for worship during the siege. Traces of the spikes have been found in renovation work since. A glance at the map of the besieged city in 1643 reveals that the church is marked but without a roof on the plan.