For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
Daniel King
Matthew 5:28 says that even having a lustful thought is committing adultery. So even if the friend of the opposite sex always keeps their mind pure in the friendship with the married person but the married partner slips just once, even if they don't act on it, adultery has been commuted. The Bible is very clear on this so I would say that relationships with the opposite sex should be limited in the extreme to keep temptation and sin a far from us as possible as the main response pointed out.
Clara Griffin
This is an interesting question because in business often men and women are traveling together for presentations and there would be times when two people could be tempted to go out together, which could lead to an affair. However, if the two people are friends and working on a project together in the presence of others that would be fine.
Making a promise (vow) to a spouse is a serious matter so, being friends with the opposite sex is setting up the scene for a temptation at some point. Personally there have been times when I was a co-chair on a committee at church with a man friend, this worked out fine for us, but in another pair of people something unforeseen could happen between them.
Danny Hickman
What makes us pick the friends we end up with? There's something about each friend we have that makes us like them. We don't cotton to everybody! It's not that we don't like the people we don't take home to meet our family; there's just nothing that we share in personalities that cause is to stick to each other. But there's something about the people we do settle down with and begin a close friendship. I'm talking about same gender friendships. We become buddies on purpose.
The only difference in a guy having a guy close friend and having a girl close friend is that we can't do certain things together that friends ordinarily do. But that is what makes having an opposite gender friend a bonus. You get to share trade secrets...
There's an old saying in my community that says, 'You don't get your meat where you get your bread.' It's a crass way of saying, 'The job is the wrong place to go shopping for a date.’ In truth, it's the place where it happens quite often. I used to tease my buddies; I'd say, 'If you want to meet your wife's boyfriend, go up to her job.'
A married guy meets a woman he likes. She's attractive and he likes her. She has a sense of humor, an infectious laugh, is smart and claims to know the Lord. They like each other. The only reason for them to not become friends is because they are opposite genders. If two men or two women meet with the same credentials it's a natural match. It still is if the people are devoted to living the truth...
Danny Hickman
"The appearance of evil."
I don't know if there's a broader stroke that can be made than a quote like this one. Almost everything we do can be cast into this bonfire!
A christian shouldn't drive too fast, show up late, leave early, chew gum in class, and on and on... and don't even think about hanging around known curfew violators unless you're seen handing out Our Daily Bread devotionals...
"The appearance of evil." It sounds theologically sound. I think it's biblical. But then there's this: "Do not judge by appearances, but judge with right judgment" (John 7:24). Jesus said that. He had healed a man on the Sabbath, and the crowd took issue with him for doing it. "The appearance of evil."
Plucking scripture out of the bible to regulate christian behavior is not good; It cheapens the Word! It turns the bible into the Sheriff's office and puts believers on wanted posters!
A pastor is seen cruising "The Strip" and "the appearance of evil" is the charge. He's there because he was asked to go and try to retrieve a prodigal who has gone astray, but that doesn't make the news, "the appearance of evil" does, however.
Abstain from every appearance of evil (1 Thess 5:22). It doesn't get much broader than this! This puts a "christian police badge" on the chest of anyone who wants to wear one! Before writing this he wrote: "Examine everything.." (vs 21). Wow... it's no wonder how the confusion started.
I don't know if Jesus could pass inspection with some of us...