Hereby know we love, because he laid down his life for us: and we ought to lay down our lives for the brethren.
1 John 3:16
Jesus has shown us by His sacrificial death on Calvary's tree, what love looks like. There was nothing in us deserving of this act of the highest form of love. God commended his own love toward us, in that, while we were yet sinners, Christ died for us (Romans 5:8). Understand this. We did not deserve this act of love. There is nothing in us to make us special to God. We were rebels, we were sinners, we spurned Him and His law. Our sinful deeds only gave the outward proof of the inner hatred we held for God.
Now as redeemed children of our heavenly Father, we are called to love each other in the same self sacrificing way that Jesus has loved us. John goes on to tell us that if we see our brother in need, we are to do what is within our capabilities to meet that need. That is how love responds to the pain and suffering around us. That is the response of Christ within us to the pressing needs we encounter on a daily basis. To withhold what is good, from one who is in need, is to refuse to love that individual (1 John 3:17-18; Proverbs 3:27). How can the love of God be in us?
Jesus calls us to the highest form of love-
"This is my commandment, that ye love one another, even as I have loved you. Greater love hath no man than this, that a man lay down his life for his friends. Ye are my friends, if ye do the things which I command you. No longer do I call you servants; for the servant knoweth not what his lord doeth: but I have called you friends; for all things I have heard from my Father I have made known unto you. Ye did not choose me, but I chose you, and appointed you, that ye should go and bear fruit, and that your fruit should abide: that whatsoever ye shall ask of the Father in my name, he may give it you. These things I command you, that ye may love one another."