Courting dating and hanging out
Close friendships by their very nature tend to involve extensive time talking and hanging out one-on-one.
They tend to involve a deep knowledge of the other person's hopes, desires and personality.
Bottom line: I believe it is difficult and rare — as a practical matter — to honor these principles in the context of a close, intimate friendship between two single Christians of the opposite sex.(For the verbally precise among you, I think such friendships between non-single Christians are also a bad idea, but that's not what we're talking about here.) Intimate friendships between men and women almost always produce confusion and frustration for at least one of the parties involved.