Purity can be a reference to many different things. It is only an adjective. It simply describes a position or credential. It can be used to describe water, life or even a process.
When we talk about purity, it is almost always in reference to something or someone else, not us. We do not want anything to corrupt us. We want good drinking water so we ask how pure it is. We want the best value, so we ask about the purity of gold. We want our children kept safe, so we discuss the challenges to purity in a relationship or other influences. Purity is a concern we have but it is most frequently about other things that might affect us. We naturally act as though we are already pure and that other things can defile us. We want others to meet our standards.
What we should recognize is that purity is not something we already have either. We are not inherently pure in our thoughts, in our ways, in our abilities or in our motives. The challenge is not simply staying pure, it is getting that way.
In John 3:25-27 we find a question of baptismal purity. In their pride, John the Baptist’s disciples thought his baptism was pure. That pride made them impure. They thought that their ministry was the greatest and when another man’s ministry was growing and his baptism was different, that there was a problem with it. Something had to be done because it did not seem exactly the same.
John the Baptist was simply an announcer, not a pastor, not the Messiah. The one who followed him was the more important and more pure form of truth and godliness. He knew that. John knew he was impure, troubled, just a man to whom God gave a most honorable task.
Don’t assess others, look at self for purity. Yes, things can potentially defile your testimony, but only because your heart is already damaged and pulled in that direction. Look at self first for impurity, then assess how you can improve your testimony. We are commanded to esteem others higher than ourselves (Phil 2:3). Too often we esteem others lower and assume we are the righteous. Only Jesus is righteous and pure. He is the standard that we must meet. He is also the standard we must encourage others to meet.