In that day, he who shall be upon the housetop, and his goods in the house, let him not come down to take it away: and he that is in the field, let him likewise not return back.
All Commentaries on Luke 17:31 Go To Luke 17
Augustine of Hippo
AD 430
For he is on the housetop who, departing from carnal things, breathes as it were the free air of a spiritual life. But the vessels in the house are the carnal senses, which many using to discover truth which is only taken in by the intellect, have entirely missed it. Let the spiritual man then beware, lest in the day of tribulation he again take pleasure in the carnal life which is fed by the bodily senses, and descend to takeaway this world's vessels. It follows, And he that is in the field, let him not return back; that is, He who labors in the Church, as Paul planting and Apollos watering, let him not look back upon the worldly prospects which he has renounced.
Lot's wife represents those who in time of trouble look back and turn aside from the hope of the divine promise, and hence she was made a pillar of salt as a warning to men not to do likewise, and to season as it were their hearts, lest they become corrupt.