The passing of the New Model ordinance was followed by the passing of a self-denying ordinance,(670) the original purport of which was to exclude all members of either House from commands in the army, but was afterwards so far modified as to compel existing officers to resign their appointments, leaving it to parliament to re-appoint them if it would. Essex, Waller and Manchester resigned, but when the time came for Cromwell, the prime mover in the re-organisation of the army, to follow suit, he and two or three others were re-appointed to commands in the new army. The immediate effect of the passing of this ordinance upon the city of London was that Pennington, who had been appointed by parliament lieutenant of the Tower, had to resign his post. The nomination of his successor was, however, left with the Common Council, who sent up the name of Colonel Francis West for the approval of the Commons (24 April).(671)
Whilst the army was undergoing a process of reformation outside London, considerable activity prevailed within the city with the object of strengthening its position. The Committee of Militia was instructed to raise a sufficient number of men to guard the city forts so that the trained bands might be free for more active duties. Large sums of money were voted to pay arrears due to gunners, "mattrosses" and workmen who had been engaged in erecting the fortifications. The sum of £500 was ordered to be laid out in the purchase of gunpowder. The scout-master for the city was encouraged in his duty of bringing information of movements of the royalist army by the payment of arrears due to him, and steps were taken to bring up the regiments of the city auxiliaries to their full complement by enlistments from the several wards.(672)
The first serious undertaking confided to Fairfax and the New Model army was the siege of Oxford. The utter uselessness of such an enterprise, whilst Charles was free to roam the country and deal blows wherever opportunity offered, failed to make itself apparent to the Committee of Both Kingdoms, which still governed the movements of the parliamentary army. The siege being resolved upon, a deputation from both Houses waited on the Common Council (16 May) to ask for assistance in furnishing a force to set out under Major-General Browne to join Fairfax and Cromwell in the undertaking.(673) Four days later (20 May), when another deputation attended, the court instructed the committee of arrears sitting at Weavers’ Hall to raise £10,000 for the purpose.(674)