Theophylact of Ohrid
Catena Aurea · Lukasevangelium 21
And take heed to yourselves, lest at any time your hearts be overcharged with surfeiting, and drunkenness, and cares of this life, and so that day come upon you unawares. For as a snare shall it come on all them that dwell on the face of the whole earth. Watch ye therefore, and pray always, that ye may be accounted worthy to escape all these things that shall come to pass, and to stand before the Son of man.
And because a Christian needs not only to flee evil, but to strive to obtain glory, He adds, And to stand before the Son of man. For this is the glory of angels, to stand before the Son of man, our God, and always to behold His face.