The Greek text has the word “But” (see Good News Bible) to introduce the second half of the contrast. Translators should probably include this word even though Revised Standard Version omits it. The situation is probably not exactly the same as that in verse 28. That is why the same verb is translated “keep silence” in verse 28 and be silent in verse 30. In the present verse “stop (speaking)” as in Good News Bible is a better translation.

The phrase another sitting by may be expressed as “another person who is sitting nearby.”

The first can be expanded to “the first speaker.” Good News Bible‘s “the one who is speaking” is clearer English. This means one of those who are referred to in verse 29a.

This verse suggests that, as in Acts 2.14, people stood up in order to take a leading part in Christian meetings.

Quoted with permission from Ellingworth, Paul and Hatton, Howard A. A Handbook on Paul’s First Letter to the Corinthians, 2nd edition. (UBS Handbook Series). New York: UBS, 1985/1994. For this and other handbooks for translators see here .