The oath of allegiance is an oath of fidelity to the sovereign in the United Kingdom. It must be taken by all persons holding important public office and as a condition of naturalization. By ancient common law, it was required of all persons above the age of 12. It was repeatedly used as a test of loyalty. In England, it was first imposed by statute in the reign of Elizabeth I (1558). The words have, more than once, been altered since. Up to the time of the revolution, the promise was "to be true and faithful to the king and his heirs, and truth and faith to bear of life and limb and terrene honour, and not to know or hear of any ill or damage intended him without defending him therefrom." The Convention Parliament enacted the form that has been in use since that time – "I do sincerely promise and swear that I will be faithful and bear true allegiance to His Majesty ..."