"By this the love of God was manifested in us, that God has sent His only begotten Son into the world so that we might live through Him.  In this is love, not that we loved God, but that He loved us and sent His Son to be the propitiation for our sins.  Beloved, if God so loved us, we also ought to love one another."

John is not suggesting that love is a challenge for us, but that it is coming from an overflow in us.

Look at the way John describes love.  Where does it come from?  How does it get in us?  What is our responsibility once it is there?

Our responsibility is simple:  love one another.  Why?  Because that is how God treated us.  We did not start this love.  We did not force it on anyone, nor was it forced on us.

But we are called to respond to the love that we are given.

The way that we respond is to love others just as God loved us.  They may not deserve it, but neither did we.  They do not have to earn it, because we did not have to earn it.  We simply give love.

If you seek righteousness - love one another.