Still more important was the adoption of the new scheme of Church government. The minister presented to a living was required to have a certificate of fitness from three persons of known godliness and integrity, one of them being a settled minister; afterwards he was to hand this certificate to certain commissioners known as Triers and to obtain their testimony that he was 'a person for the grace of God in him, his holy and unblamable conversation, as also for his knowledge and utterance, able and fit to preach the gospel'. Having become an incumbent, he was liable to expulsion by a local body of Ejectors for immorality or for holding blasphemous or atheistical opinions. As long as he was maintained in his post, he might uphold any Puritan system he pleased and organise his congregation on the Presbyterian, Independent, or Baptist system, if he could persuade them to follow him. Those persons, whether lay or clerical, who objected to the system upheld in their parish church, were at liberty to form separate congregations--gathered Churches, as they were called--at their own discretion. Later on, towards the close of 1655, Oliver's tolerant spirit gave way to the return of the Jews, who had been exiled from England since the reign of Edward I. A few Unitarians were no doubt excluded from the benefits of his toleration. Moreover, the Society of Friends, now rising into importance under the leadership of George Fox, was also threatened with exclusion as presumably guilty of blasphemy, though the Protector himself not infrequently interfered on behalf of its members. Even if this had been otherwise, the Society put in no claim for participation in a legal support or even for acknowledgment by the State.