So yes, of course. God is love. That is a great neccesary and life giving truth. And i love it. But it what sense is is a life giving and neccesary thruth? What does it mean that God is love? How is this love expressed. In the quote about Steve Chalke says he's been accused of 'not putting it in context'. Well thats do that now, and lets see if the argument against, particularly in this case penal substitution is affected in any way by the context of the rest of the passage:
Anyone who does not love does not know God, because God is love. In this the love of God was made manifest among us, that God sent his only Son into the world, so that we might live through him. In this is love, not that we have 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.
So John's argument seems to be 1) if we don't love each other we don't know God, why? Because 2) God is love. And how can we know His love? What does His love look like? 3) He sent His Son to be the propitiation for our sins. 4) Look how much God loves us, so love each other.
So it seems from this that 'God is love' far from giving trouble to the doctrine of penal substitution is actually based on that doctrine. God is love. This is what His love looks like, that He sent His Son to bear our sins on the cross. God is love seems to lead us straight to penal substitution. And it seems to suggest that God is love means that God will give us Himself, that God's greatest gift in His love is Himself in His Son. Why? Well what did the cross achieve for us? Forgiveness of sins? Yes,
Infinitly neccesary but not ultimate. It's not ultimate because the cross is not about God. So what difference does that make? Well when a God ultimatly concerned with His own glory (as we also see from this verse, God being love demonstrates Father loves Son, Father loves Holy Spirit, Son loves Father and Holy Spirit and Holy Spirit loves Father and Son) sends His own Son to die, it's going to be for God glorifying reasons. It's going to be to bring us to Him, so we can worship, enjoy and praise Him. And thats what it does.
In Heaven we will love the Son as the Father does, and vice versa. This love withh be eternal, infinite, white hot, overwhelmed with joy. And, for us, as we continue to see the glory of Jesus unfold for eternity, it will be a love that grows and grows. How does this happen? How can jesus possibly win this for sinners like you and me? By what He did on the cross. By removing every barrier, every sin that stood between us and this all satisfying, white hot joy filled relationship with the Father.
So yes, God is love. All day every day. But we can only know and taste this because in His love, because God is love, He sent Jesus, to bare the wrath that we deserve on our behalf, so that we might spend eternity caught up in, and experiencing this Father, Son, Holy Spirit love.