Western society holds strongly to some foundational values like equality, freedom, kindness, progress, and others. But all these values have Christian roots. Helping our non-Christian friends see this can help them move from unbelief to saving faith.
Recommended Resources
The Air We Breathe: How We All Came to Believe in Freedom, Kindness, Progress, and Equality by Glen Scrivener
3 2 1: The Story of God, the World and You by Glen Scrivener
The Case Against the Sexual Revolution by Louise Perry