Question:I saw that the church only met on the first day of the week to gather and worship. Does this mean that I sin if I go to youth groups on Wednesdays (while still going to church on Sunday), or if my school has weekly mandatory chapel services on Thursdays?
There are various acts of worship that a congregation is involved in doing: prayer, singing, teaching, giving, and partaking of the Lord's Supper are the main elements. Some of these things are not restricted to only on Sundays when the church is gathered together, some of these things are restricted.
Prayer is done when the church is assembled (Acts 2:42), but it is also done by Christians at other times (Acts 11:5).
Singing is done by the congregation when assembled (I Corinthians 14:26), but is also done by Christians at other times (James 5:13).
Teaching is done in the worship (Acts 2:42), but it is also done at other times as well (Acts 18:26).
But when we come to giving and partaking of the Lord's Supper, we find that these two acts of worship cannot be done individually and that they were only done on the first day of the week (I Corinthians 10:16-17; 16:1-2; Acts 20:7).
Therefore, there is nothing wrong for Christians gathering together to study on days other than Sunday or to engage in songs and prayer. However, it would be wrong to take up collections for the church at these gatherings because that is to be done on the first day of the week (I Corinthians 16:1-2). It would be wrong to partake of the Lord's Supper, since the only day Christians partook of it was on the first day of the week (Acts 20:7).