Why can’t we cross between the Altar and the East when the Lodge is at labor?

From a symbolic perspective, the Three Great Lights transmit their Light to the Master, whose duty it is to disseminate that Light to the Brethren in the Lodge. When someone crosses the East, that transmission of Light is interrupted. There are, of course, times when this restriction is impracticable, which is why we move freely about the Lodge during Degree Rituals and the Master can grant freedom of the Lodge to anyone he chooses, such as a Brother giving a talk or presentation. In all considerations such as these we must use common sense and avoid adopting a fundamentalist attitude towards our Rituals and traditions to such an extent that there is a negative effect on the work and operations of the Lodge.