The Spirit of the LORD shall rest on him: The Spirit of wisdom and understanding ... (Isaiah 11:2)This may seem obvious -- and sometimes the most obvious things are the ones we overlook. (Really, being proficient -- more than a beginner -- in any skill, means having become so accustomed to certain basic things that we no longer have to think about them any more. And so we don't. Every level of expertise carries its own blind spot, in that way.) If I look back on every conversation I've ever had, and look forward to every conversation I expect to have, all those conversations share one thing: a common language. The other person and I could understand each other, if we tried. Every long-term friendship I've ever had was with someone that I could talk to, or write with, in a language that we both understood. I've had some casual interactions with people who don't speak the same language; you can get a certain distance with signs and body language and facial expressions. But there is only so far we will get without a common language.
At Pentecost, the gift of languages was a gift of communication, a gift of understanding, a gift of including all people. It is a gift of fellowship ("the fellowship of the Holy Spirit") which begins at the basic level of understanding each other.
Like all the great gifts, even understanding must take its direction from love or it becomes unwelcome. Consider how much Amazon and google "understand" us from keeping close track of our actions, and how much Big Brother "understands" us from our communications, for examples of how someone can "understand" without any real understanding of us as people, or any wish to understand us as people. I do not mean to start anyone worrying about Amazon, google or Big Brother; I mean to mention that in our own small way, we're hardly any better if all our understanding is without love. As a follower of Christ, I want to understand my neighbor in a way that helps me see them through the eyes of love, so that my understanding is a gift. We all desire that kind of understanding. May God grant that the Spirit of wisdom and understanding help us.