cchang wrote:I guess we called them to be a Teacher in EQ and that's what was confusing since offices don't require sustaining and only setting apart.
I'm not sure what you mean by 'offices'. The term office is primary used in connection with the priesthood to denote either Deacon, Teacher, Priest, Elder, High Priest, Bishop, Patriarch or Apostle. Teacher in this context is not someone who teaches a class but someone who has been ordained to the office of a Teacher. They are not set apart as a Teacher but ordained. And they do need to be sustained by the membership of the ward, usually in sacrament meeting. But someone who is already an Elder cannot be then ordained to the office of a Teacher because they already hold a higher priesthood office. So if someone is called to teach in Elders Quorum meetings then they are an instructor.
There are certain assignments that may be made (specifically some assignments to High Councillors and ministering brothers and sisters) which do not require either sustaining or setting apart. But the only callings listed in the Chart of Callings which require setting apart but not sustaining are auditors, stake welfare specialists and mission presidents.