1 John 4:7 (NKJV)
7 Beloved, let us love one another, for love is of God; and everyone who loves is born of God and knows God.
I wouldn't put my assurance of salvation on that verse because some people appear to love when their love is not 1 Corinthians 13 love. I have seen people described as knowing love when they are the opposite of Paul's definition. You cannot be a schemer and a gossip and a liar and know true love. People easily deceive themselves.
You can care about abused women and adultery and children in wrecked homes etc... (Delivering my body to be burnt) and still not know real godly love.
KJV 1Jn 4:7 Beloved, let us love one another: for love is of God; and every one that loveth is born of God, and knoweth God.
He is basically reminding them to be toward one another who God has called them to be toward one another as His - to love one another.
Why?
Because love is of God and they are of God. Thus, they ought to love one another just as He loved them.
Case in point...
1Jn 4:8 He that loveth not knoweth not God; for God is love. 4:9 In this was manifested the love of God toward us, because that God sent his only begotten Son into the world, that we might live through him. 4:10 Herein is love, not that we loved God, but that he loved us, and sent his Son to be the propitiation for our sins. 4:11 Beloved, if God so loved us, we ought also to love one another.
Or, as Paul said to the Galatians...
Gal 5:13 For, brethren, ye have been called unto liberty; only use not liberty for an occasion to the flesh, but by love serve one another.
In other words, there is simply no room in the Christian walk for animosity towards others, or any other notions of the fleshly mind that the fleshly mind comes up with and would have us believe.
I remember once all of a sudden having some odd, out of nowhere, traumatic flashback from some past event.
I'm going through it; and therefore buying into it, when it dawns on me "wait a minute - this is no longer who I am in Christ! This is absolute nonsense! I've been freed from the carnal mind! I've been made complete in Christ! I'm this in Him! I'm that in Him!" and so on...
And just like that, this Pauline, spiritual self-counseling that is so built into the Scripture, delivered me from that nonsense of the fleshly mind, right then and there.
Well, John is doing something like that - he is focusing them on who they are with one another, who they can be with one another because they are of God.
Not in order to be of God. Rather, because they are of God.
He is describing who they can be towards one another because of who God has made them be in His Son, redemptively...
1Jn 4:6 We are of God: he that knoweth God heareth us; he that is not of God heareth not us. Hereby know we the spirit of truth, and the spirit of error. 4:7 Beloved, let us love one another: for love is of God; and every one that loveth is born of God, and knoweth God.
Be who ye are, beloved!
Love one another!
Rejoice in its opportunity!
What opportunity?
The same one the Lord saw when He was despised by those He died in His love for them even as they despised Him!
1Jn 4:10 Herein is love, not that we loved God, but that he loved us, and sent his Son to be the propitiation for our sins. 4:11 Beloved, if God so loved us, we ought also to love one another.