John 13:35 KJV
By this shall all men know that ye are my disciples, if ye have love one to another.
John 13:33–37 KJV Chapter Context
33
Little children, yet a little while I am with you. Ye shall seek me: and as I said unto the Jews, Whither I go, ye cannot come; so now I say to you.
34
A new commandment I give unto you, That ye love one another; as I have loved you, that ye also love one another.
35
By this shall all men know that ye are my disciples, if ye have love one to another.
36
Simon Peter said unto him, Lord, whither goest thou? Jesus answered him, Whither I go, thou canst not follow me now; but thou shalt follow me afterwards.
37
Peter said unto him, Lord, why cannot I follow thee now? I will lay down my life for thy sake.