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.
This brings me to my second argument against intimate one-on-one friendships between brothers and sisters in Christ. Men and women who are not called to long-term singleness and celibacy have a strong desire for companionship with a member of the opposite sex. As I've discussed before, Scripture seems to consider marriage (and children) to be a normal part of the progression toward biblical manhood and womanhood (see, among others, Genesis -28; -24; Matthew -41; Luke -36).Yet even with all this deep communication going on, at least one aspect of these friendships inherently involves a mixed message.No matter how clearly one or both of you have defined what's happening as "just friends," your are constantly saying, "I enjoy being with you and interacting with you in a way that suggests marriage (or at least romantic attraction)." The simple reality (of which most people are aware, whether they admit it or not) is that in the vast majority of these types of relationships, one of the parties involved either began the "friendship" with romantic feelings for the other person or develops them along the way.As you probably know, I believe Scripture to teach that engaging in the types of emotional intimacy and companionship involved in close male-female friendships — outside of marriage and for their own sake — is wrong (see else I've ever written for Boundless).
But even if you don't accept that premise, such intimacy is still inadvisable in the sense that it delays and discourages marriage, which Scripture unambiguously calls good and right.
They tend to involve the sharing of many aspects of each other's daily lives and routines.