Langham Partnership International is encouraging Christians not to be put off becoming Christlike.
A survey of nearly 2,000 British evangelicals found that more than half (54%) are concerned that "becoming Christlike will increasingly alienate Christians from the culture around them".
Peter Brierley, who carried out the survey also suggested a "lack of priority in evangelism", after around three-quarters (76%) of lay evangelicals were found to have been Christians for more than 20 years.
Further underpinning his view, evangelism was identified as only the fourth most important key dimension of church life, out of six options.
The Bible is still deemed to have a significant influence on faith development and shaping attitudes to the family and world, and prayer is widespread, with 71% of the laity praying every day.
The majority of lay evangelicals also said their faith had grown in the past year as a result of fellowship and church teaching in services or house groups.
Commenting on concerns about Christlikeness, executive director at Langham Ian Buchanan said it was not clear whether the data reflected an "uncomfortable hesitation" or simply an "understandable confirmation that most Christians are aware of the fact that their ongoing transformation will inevitably put them at odds with the growing post-Christian culture" in the UK.
"Langham Partnership would like to think that it is the latter response that is emerging in the church but only time will tell just how well the church in the UK responds to cultural change on our islands," he said.
"Certainly the call of the gospel for God's people to become salt and light in their region of the world, for the sake of God's mission, has not been rescinded."
The survey was carried out for Langham to mark the launch of a major new campaign encouraging Christians to go deeper in their faith and discipleship during 2013.
Church leaders share their thoughts on Christlikeness alongside other free resources at www.9aday.org.uk