Charles Ellicott Commentary Matthew 23:6

"and love the chief place at feasts, and the chief seats in the synagogues," — Matthew 23:6 (ASV)

The uppermost rooms — This is better translated as the first places. The word “room” had this meaning when early English Bibles were translated, but today it simply means “chamber.” Specifically, these were the primary places on the couches or ottomans where guests reclined, positioned nearest to the host. These seats of honor were assigned to the most favored guests, as seen in the case of “the disciple whom Jesus loved” (John 13:23).

The chief seats in the synagogues — These seats were at the upper, or Jerusalem-facing, end of the synagogue, which corresponds to the east end of most Christian churches. This is where the ark, the chest containing the Law, was kept. These seats were given, either by common agreement or by the synagogue elders, to those most distinguished for their devotion to the Law. As such, they were coveted as a sign of religious standing.