What is THE MARK?

 At the close of his ministry, Jesus looks forward to his death on the cross, the open tomb and the ascension. Knowing that he is about to leave, Jesus prepares his disciples for what is to come. It is here that he makes clear what will be the distinguishing mark of the Christian:

33[Dear] little children, I am to be with you only a little longer. You will look for Me and, as I told the Jews, so I tell you now: you are not able to come where I am going.

    34I give you a new commandment: that you should love one another. Just as I have loved you, so you too should love one another.

    35By this shall all [men] know that you are My disciples, if you love one another [if you keep on showing love among yourselves].

This passage reveals the mark that Jesus gives to label a Christian not just in one era or in one locality but at all times and all places until Jesus returns.

Notice that what he says here is a command which includes a condition:

”A new command I give you: Love one another. As I have loved you, so you must love one another. By this all men will know that you are my disciples, if you love one another.”

An if is involved
If you obey, you will wear the badge Christ gave
It is possible to be a Christian without showing the mark, but if we expect non-Christians to know that we are Christians, we must show the mark.

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