The world is reeling toward the end quickly (I personally think Jesus return is a few decades away, but it could be anytime). BUT, the rest of the verse above says,
but the Lord rises upon you and his glory is seen upon you (id.)
So as the world gets darker, our lights shine brighter. So the Lord wants His people to know Him more intimately and also to know what's going on around them.
But you, brethren, are not in darkness, that that day should overtake you as a thief. You are all the children of light, and the children of the day: we are not of the night, nor of darkness. Therefore let us not sleep, as do others; but let us watch and be sober (1 Thess 5:4-6).
The Lord wants us to know the truth about what's coming so that His children will be comforted and not afraid of the wrath to come.
For God has not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ, who died for us, that, whether we wake or sleep, we should live together with him. Wherefore comfort yourselves together, and edify one another, even as also you do (1 Thess 5:9-11).
Nice...