Following Peter’s message at Pentecost (Acts 2:14-36), his audience asked him what they should do (2:37) in view of what he had preached and the effect that his message had on them. Luke records Peter’s response to their request in two parts: (1) 2:38-39 and (2) 2:40.
In the latter, Luke tells us that “with many other words did he testify and exhort, saying, ‘Save yourselves from this untoward generation.'” Because of Peter’s ministry on this occasion, including his lengthy final appeal, about 3000 people gladly received his word, and they were baptized (2:41a). In that same day, they were added to the apostles (2:41b).
Peter’s ministry included more than just proclamation of his message; he forcefully exhorted his hearers at length to respond properly to what they had heard. He thus exemplifies for us how we should minister the word to people: preach the message and then challenge people “with many other words” to respond correctly.
Based on this teaching, a lengthy invitation at the end of an evangelistic message should not automatically be viewed as a human expedient intended to manipulate people to respond. Although such an invitation could be abused by using it in a manipulative manner, we should not regard giving a lengthy invitation as an inherently unjustified practice.