Did you spot how many metaphors Paul mixes here? He begins with the ‘day of the Lord’ which is like a ‘thief’ (v 2), an invasion (v 3) and ‘labour’ (v 3). Like the disciples before them (Acts 1:6,7), the Thessalonians wanted to know when this day would come. I can sympathise – I like to know ‘when’ so I can plan!

Paul’s answer is that we don’t need to know; we need to be ready. The ‘day of the Lord’ will come – but the day of God’s kingdom has already dawned. Once again Paul returns to the gospel: ‘he died for us so that … we may live together with him’ (v 10). Don’t worry about when Jesus will return, Paul says, but learn to live the life he has won for you (v 8).

Again he urges them to ‘encourage one another’ (v 11; 4:18). Why? Because keeping focus is hard! We need to remind one another of the truth, uphold one another as we walk and help one another face the light.

‘The Lord is my light and my salvation – whom shall I fear? The Lord is the stronghold of my life – of whom shall I be afraid?’¹

I’m intrigued by the behaviour of some motorists on a stretch of road near where I live. They speed where there are no speed cameras, slow down to pass the camera, and then speed up again. I wonder, if the cameras were hidden, if the bad drivers would be caught and others encouraged to comply with the speed limit consistently.

Paul might be unfamiliar with this illustration, but he would definitely understand the psychology behind it. He resists any pressure to speculate about specific ‘times and dates’ of the day of judgement (v 1), observing that the day of the Lord (like a hidden camera) will arrive unexpectedly, as Jesus made clear in his own teaching.² Unbelievers (like speeding drivers) might assume that the system doesn’t apply to them, but they will certainly be caught (v 3). On the other hand, believers, like the Thessalonians, need not worry about being caught out. They are children of light, chosen not to ‘suffer wrath’ but to ‘receive salvation’ through Jesus Christ (v 9). Their whole lives are preparation for the final day, as they walk in accordance with their calling. They are like the consistently careful drivers.

There is both encouragement and challenge for us in Paul’s message. Whatever our circumstances or however we feel, we can have confidence that we do not ‘belong to the night’ (v 5), but to Christ. He has saved you – and that’s a fact! But there’s also a challenge. Does the whole of your life reflect your identity as a child of light, or are there parts which lurk in the shadows, lacking in faith, love or hope? Take heart: according to Paul, we can ‘put on’ these virtues that are our spiritual inheritance, just as a soldier ‘puts on’ a breastplate, or helmet (see v 8). What do you need to put on today?

Imagine this is your last day, week or month of life. How might this change how you live?

¹ Ps 27:1  ² Matt 24:36; Mark 13:32