John Gill Commentary Luke 11:24

"The unclean spirit when he is gone out of the man, passeth through waterless places, seeking rest, and finding none, he saith, I will turn back unto my house whence I came out." — Luke 11:24 (ASV)

When the unclean spirit is gone out of a man
That is, the devil, who is in, and works in the children of disobedience, whether under a profession of religion or not; whose hearts are unclean like himself, wherefore there he delights to dwell; and so the Ethiopic version renders it, "the evil demon": who may be said to go out of a man in appearance, when he outwardly reforms and takes up a profession of religion.

He walks through dry places ;
or "a desert", as the Ethiopic version; to which the Gentile world is sometimes compared in the Old Testament (Isaiah 35:1) (Isaiah 41:18Isaiah 41:19) (42:11) to which Satan might go, being disturbed in Judea, through the many dispossessions by Christ; or rather leaving for a while the Scribes and Pharisees, who outwardly appeared righteous before men, he went to the Gentiles;

seeking rest, and finding none ;
being also made uneasy among them, through the preaching of the Gospel, which was sent unto them after Christ's resurrection; and not being able to keep his place in the hearts of men, nor do the mischief he was desirous of.

He says, I will return unto my house, from where I came out ;
to the Jews again, who were blinded and filled with rage and enmity to the Gospel by him, and whom he instigated to persecute the apostles of Christ, and preachers of the word, wherever they came; (See Gill on Matthew 12:43) and (See Gill on Matthew 12:44).