Matt. 24:32-44 (NRSV)
32 'From the fig tree learn its lesson: as soon as its branch becomes tender and puts forth its leaves, you know that summer is near. 33So also, when you see all these things, you know that he is near, at the very gates 34Truly I tell you, this generation will not pass away until all these things have taken place. 35Heaven and earth will pass away, but my words will not pass away. 36'But about that day and hour no one knows, neither the angels of heaven, nor the Son, but only the Father 37For as the days of Noah were, so will be the coming of the Son of Man. 38For as in those days before the flood they were eating and drinking, marrying and giving in marriage, until the day Noah entered the ark, 39and they knew nothing until the flood came and swept them all away, so too will be the coming of the Son of Man. 40Then two will be in the field; one will be taken and one will be left. 41Two women will be grinding meal together; one will be taken and one will be left. 42Keep awake therefore, for you do not know on what day your Lord is coming 43But understand this: if the owner of the house had known in what part of the night the thief was coming, he would have stayed awake and would not have let his house be broken into. 44Therefore you also must be ready, for the Son of Man is coming at an unexpected hour.
For me, a central element in the commemoration of the Advent season is learning to expect the arrival of the thing I cannot imagine at the time when I cannot imagine it. After all, we are talking about the coming of the Lord here. And God is nothing if not unpredictable. If our eyes could see, ears hear, or hearts imagine what God is up to, then we... well, we'd be God.
Listen to the competing images in the section of scripture for today's reading. The lesson of the fig tree is that there are signs that point to the change that's coming. The lesson of the thief is that some events are by their very nature unexpected. So, in Advent, I guess what we are looking for are the signs that God is up to something. And since we know that because what God does always disrupts the normal and mundane (cooking, eating, working, sleeping), we might as well get prepared for the shock of it. Everything will be normal until it isn't.
Be ye also ready.