God intended His church to stand out, not to be asleep, so that others may come to know Him. Satan has a lullaby - apathy and complacency. A lack of interest, a lack of concern, a lack of enthusiasm. The devil is not concerned that we’re in church, in fact he encourages is so long as we are ineffective while we do it. If we can attend church but be apathetic about the lives of other people, then we are no danger to him.
From the beginning of time God has sounded an alarm to wake His people and make them effective. The people Isaiah was preaching to in about 700 BC are not any different than we are now - they have gotten sleepy and need to have an alarm raised to draw them to attention.
Scriptures used: Isaiah 60:1-3, Proverbs 6:6-11