This verse refers to a specific incident in Ephesus, described in Acts chapter 19. Let's break it down:

"Certain also of the Asiarchs": Asiarchs were wealthy and influential men in the Roman province of Asia (modern-day western Turkey). They were responsible for organizing and funding public games and festivals, which often included religious ceremonies honoring Roman gods and the emperor. Being an Asiarch was a prestigious position.

"being his friends": This indicates that some of the Asiarchs were friendly towards Paul, who was preaching Christianity in Ephesus. Perhaps they respected him as a person, or maybe they were sympathetic to his message to some extent.

"sent to him and begged him not to venture into the theater.": Ephesus had a massive theater that could hold tens of thousands of people. In this context, a riot was brewing due to the economic impact of Paul's preaching on the silversmiths who made idols of the goddess Artemis (Diana). These Asiarchs, aware of the volatile situation and concerned for Paul's safety, sent a message urging him not to go to the theater.

Therefore, the verse means that some of the prominent and influential Asiarchs in Ephesus, who considered Paul to be a friend, sent him a warning and pleaded with him not to go to the theater because they knew there was a dangerous mob gathered there due to the controversy surrounding his teachings.

The verse highlights:

Paul's growing influence: Even powerful figures in the community knew of him and cared about his well-being.
The intensity of the opposition: The situation was so heated that even Paul's friends were worried about his safety.
The role of personal relationships: Despite the overall conflict, some people were willing to extend friendship and protection.
The importance of wisdom and prudence: Paul, heeding their advice, likely avoided a potentially fatal confrontation.