The gabbai runs the synagogue service from the floor, and the office is a practical one of management and good order rather than of learning or sanctity.
Assigning the honours
The gabbai oversees the conduct of the service, and his most visible task is the assignment of the honours: deciding who is called up to the Torah for each portion, who opens the ark, who lifts and dresses the scroll, and who leads which section, and he stands beside the reader to follow the text and quietly correct any error in the chanting, since the public reading must be exact. The office thus keeps the service running smoothly and correctly, a role of coordination that is essential to the orderly worship of the congregation.
A lay office of service
The gabbai is a lay member of the congregation, not a rabbi or a cantor, and the office is one of service to the community, sometimes elected, sometimes appointed, and often held by those with a good knowledge of the ritual and a willingness to take on the work. The word has also denoted the treasurer or administrator of a congregation or of a charitable fund, and in Hasidic communities the gabbai is the aide who manages the affairs of the rebbe. In all its uses the office is practical and administrative, the person who sees that the business of the community, and above all the good order of its worship, is properly carried on.