Last Sunday's Watchtower admits (p. 17) that "we are not under the Mosaic Law." But in the next paragraph it says that just as the tithing arrangement was not optional for the Israelites, meeting attendance is also not optional for Christians.
The first page of the February 2004 Kingdom Ministry tells us why. After talking about how Christian families should give priority to attending meetings regularly, it encourages us to look at things from Jehovah's standpoint:
"By gathering wood on the Sabbath, one Israelite man deliberately failed to consider Jehovah's point of view. He may have reasoned that he was providing for his family or that it was just a small thing. By means of the judgment rendered, however, Jehovah showed that pursuing mundane activities during times designated for worship is a serious matter." Numbers 15:32-36 is cited. Verse 35 and 36 says: "Without fail the man should be put to death, the whole assembly pelting him with stones outside the camp. Accordingly the whole assembly brought him forth outside the camp and pelted him with stones so that he died, just as Jehovah had commanded Moses."
No excuses - household duties, secular work or school work should never encroach on time set aside for the worship of Jehovah. Some worker's trade shifts with workmates, seek a more suitable job, or simplfy their life-style. Some parents explain to teachers that their children cannot complete their assigned homework because attendance at Christian meetings is a priority for their family.