Final answer:
Christian worship services have traditionally been held on Sundays, the day associated with the resurrection of Jesus Christ.
Step-by-step explanation:
The worship services in question are Christian in nature. Historically, Christian worship services have traditionally been held on Sundays, which is considered the Lord's Day and a day of rest. This tradition is rooted in the resurrection of Jesus Christ, which is believed to have occurred on a Sunday. Additionally, the excerpt mentioning the Sabbath school refers to educational gatherings that also occurred on Sundays. Over time, some Christian sects and denominations have held services on other days as well, such as Wednesday night prayer meetings, but Sunday remains the primary day for Christian worship services.