Proverbs 27:17 (ESV)
¹⁷  Iron sharpens iron, and one man sharpens another.

Our interaction with each other as brethren is crucial to our spiritual development in Christ.  We need to sharpen each other from time to time.  When men challenge each other, it can lead to growth.  There are two ways that brethren can challenge each other.

First, brethren can challenge the knowledge of one another.  The word of God should be a major part of all our lives as Christians.  We should want to be like Apollos, that is, mighty in the scriptures.  Remember, faith comes by hearing the word of God (Romans 10:17).  That is why the devil does all he can to limit our intake of God’s word.  If we are going to stand against the wiles of the devil, having a good knowledge of the word is going to be a major factor.

One way my knowledge of God’s word can increase is by being challenged by brethren.  I can make anything I conclude scripturally sound right in my own mind.  When I argue a point about a passage with myself, I always win the argument.  Sometimes I need someone else’s perspective on a passage.  There will be times when we come home from a Bible class that I have taught, and my wife, Janice, will let me know that she disagrees with a conclusion I came to concerning a passage.  Of course, I think that I am right, and she is wrong, at least at first.  Inside I am a little offended that she dares to challenge my studied conclusion.  However, Janice, having been a student of the Bible most of her life, has a good understanding of the Word, and soon I find myself doubting the strength of my argument.  In the end, she might convince me to change my position on the passage, or I will conclude that I am right, but the point of it is this—one way or the other, her challenging me sharpens my view and helps me to grow in knowledge.

One of the few things I enjoyed about doing a call-in radio program for years is that it challenged my knowledge.  It is one thing to preach to an audience that mostly agrees with me every week, and something else to speak to an audience made up of some people who want to find something wrong with my teaching before I even open my mouth.   The former is comfortable, but the latter helped me to grow because iron sharpens iron.

Second, this proverb is true concerning our overall Christianity.  It is good to be challenged by other Christians who are stronger than we are in certain areas.  For example, I have a friend who is great at sharing the gospel with strangers.  I take note of how easy it is for him to walk right up to somebody and start a conversation about the bible.  His willingness to talk to others about their salvation puts me to shame.  I always find myself thinking, I need to be more like him when it comes to talking to others.  I need to be more evangelistic.  He never says, “Don, you need to do better.”  Instead, he challenges me with his actions.

There are times when I am with others who are not as strong as I am evangelistically, but that does not sharpen me.  What helps me the most is being around those who are stronger than I am in that area.  Being around other Christians who are strong spiritually is good, even if it makes us feel in some ways inadequate.  It sharpens us and makes us want to do better.  That is profitable spiritually.  It was the Hebrews writer who said, “And let us consider how to stir up one another to love and good work” (Hebrews 10:24).  When another Christian challenges you, do not get mad about it.  Instead, remember the proverb, “iron sharpens iron,” and be thankful that you have been given the opportunity to grow.

As you wind down for the night, think about these things.