When we are born again, we are born into a family. We become a child with many brothers and sisters. We belong to each other and we are members of the Body of Christ. Christ is the head of His body and in Him—
The "I" becomes "we"
The "me" becomes "many"
The "one" becomes "one another"

In the book of Romans, the Apostle Paul tells us we are to…
Be kind to one another;
Honor one another;
Build up one another;
Be in harmony with one another;
Have sympathy for one another;
Receive one another;
Counsel and instruct one another;
Love one another.

1 Thessalonians

3:12 NKJV

Love Is Our Mark

A new commandment I give unto you, That ye love one another; as I have loved you, that ye also love one another. By this shall all men know that ye are my disciples, if ye have love one to another.John 13:34-35

Jesus not only told the them to love one another, but that this love would serve as a visible way to identify disciples of Christ.

He left them with a commandment to love that would leave them marked, that should leave us marked.
Marked by compassion for one another.
Marked by a spirit of forgiveness.
Marked by a desire to serve.
Our love for one another is an identifier that marks us as His.

Being a disciple of Jesus marks you: not by the cross around your neck or the songs on your radio or your presence in the pew. You're marked with His love, which left unchecked and unhindered should permeate your life and relationships, His fingerprint upon you.