The Bible does not set a service timetable
Scripture calls believers to keep gathering and encouraging one another, especially as they await Christ's return (Hebrews 10:25). Yet it does not give a rule saying every church must meet on Sunday morning, Sunday evening, or both. A church can faithfully obey that call with different patterns of meeting.
Paul teaches that Christians may reach different conclusions about particular days while seeking to honour the Lord (Romans 14:5-6). That principle does not make gathering unimportant. It does mean that the exact schedule is not a test of faithfulness.
Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.
Early Christians sometimes met in the evening
One well-known example comes from Troas. The disciples gathered on the first day of the week to break bread, and Paul spoke with them through the night (Acts 20:7). The room had many lamps, which fits an evening gathering (Acts 20:8).
That story shows that evening worship is not strange or unbiblical. Still, Acts describes what happened in Troas on that occasion. It does not turn Paul's long farewell meeting into a command for every congregation to copy.
And upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight.
Why churches choose to meet again
A second service can give a congregation more space to pray, sing, hear Scripture explained, share communion, or welcome people whose work or family duties kept them away earlier. It may also create a quieter, more informal setting than a larger morning gathering.
For some churches, Sunday evening is a chance to return to God's word with fewer time pressures. For others, it is simply a long-loved rhythm of fellowship. The aim should be mutual strengthening, because believers are meant to use what God has given them to build each other up (1 Corinthians 14:26).
Freedom, not pressure
If your church has an evening service, you can receive it as an invitation rather than a burden. Going may be a meaningful way to grow in worship and relationships. If you cannot attend, that does not mean you have failed God.
Churches also need wisdom about what genuinely serves their people. Paul urged the Corinthians to let their gatherings be done in a way that builds up the church (1 Corinthians 14:26). Whether a congregation meets once on Sunday or more often, the heart of the matter is meeting around Christ, his word, prayer, and loving encouragement.
One man esteemeth one day above another: another esteemeth every day alike. Let every man be fully persuaded in his own mind. He that regardeth the day, regardeth it unto the Lord; and he that regardeth not the day, to the Lord he doth not regard it. He that eateth, eateth to the Lord, for he giveth God thanks; and he that eateth not, to the Lord he eateth not, and giveth God thanks.