Christians disagree all the time about all sorts of things but it can be worrying when they can't agree about things that are centrally important to what it means to be a Christian, have a real relationship with God, forgiveness, a place in heaven, etc. After all, if Christians can't even agree amongst themselves about what makes them Christians then why bother with Christianity at all?
I'm super-motivated to discover real truth and to know for sure that it's really true. Without know-able truth, we're all just guessing and we may as well believe anything that anyone comes up with! Who's to say we've got it wrong if it's impossible to know for sure? I'm personally convinced that God has revealed truth to us in the pages of the Bible we have today and particularly in the person of his Son, Jesus Christ (Hebrews 1:1-4). If you want to know why I'm so convinced about this, ask me and I'll have to write about it! For now, I'm just letting you know that this is how I'll be measuring what I consider and understand to be truth - by looking at what God has said to us in the Bible and what he has shown us through his Son, Jesus.
So here's the first idea from my friend... 'Christ's afflictions lacking? (Colossians 1:24)'...
I'm left wondering a bit about what my friend is getting at here but I'm guessing it has something to do with the sufficiency of what Jesus did on the cross. Paul seems to be suggesting that Jesus' suffering was insufficient in some way but is this really what he is saying? Did Jesus do everything necessary for us to be saved, rescued from sin, death and hell into a relationship with God? Or do we need what Jesus did, plus something more?
The Bible is pretty clear that what Jesus did for us all on the cross was and is absolutely enough to secure the offer of free forgiveness and eternal rescue for anyone who puts their trust in him. It says we must believe in him to receive eternal life and be saved (John 3:16, Acts 16:30-31). It promises forgiveness for those who ask (1 John 1:9), and it describes Jesus as the one who perfects or 'finishes' our faith (Hebrews 12:2). Jesus said 'It is finished!' when he died on the cross (John 19:30). The original greek shows us that this was a triumphant statement rather than a sigh of relief. It was more like, 'It is accomplished!' or 'It is done!' or even 'Eat it Satan - I've beaten you!' (if I use my imagination slightly!).
After all Jesus went through, all the fulfilled Old Testament prophecies, all that the New Testament says about his death and resurrection - the idea that he didn't suffer enough or that his sufferings need topping up somehow by our own efforts just seems to be ridiculous.
We must understand what Paul is writing in Colossians 1:24 in the context of the rest of the Bible. We can't ignore what Paul is saying (it is still God's word to us) but neither can we accept the most obvious meaning of a Bible verse if that means it flies in the face of what God says throughout the Bible very clearly. God doesn't contradict himself.
The true meaning of what Paul is saying in Colossians 1:24 is more likely to be that he is identifying with the sufferings of Christ as he suffers for the church too. He's not completing, topping up or finishing off the act of salvation for Jesus. He's simply being like Jesus himself by suffering obediently for the love of his people. When he says 'I fill up in my flesh', he's saying - 'I want to be as much like Jesus as I can and I want to fill up my life with what he did!'