Saying, let us alone,.... Not that there were more spirits in him than one, as the whole account shows; but he includes the rest of the devils in that country; See Gill on Mark 1:24.

What have we to do with thee (τί ἡμῖν καὶ σοί)?

Lit., what is there to us and to thee? i.e., what have we in common? So Wyc.

{6} Saying, Let us alone; what have we to do with thee, thou Jesus of Nazareth? art thou come to destroy us? I know thee who thou art; the Holy One of God.

(6) Christ astonishes not only men, be they ever so stupid, but even the demons as well, whether or not they want to be.

4:33-37 In the synagogue there was a man. See notes on Mr 1:21-27. Matthew omits this account.

4:34 What have we to do with thee - Thy present business is with men, not with devils. I know thee who thou art - But surely he did not know a little before, that he was God over all, blessed for ever; or he would not have dared to tell him, All this power is delivered to me, and I give it to whomsoever I will. The Holy One of God - Either this confession was extorted from him by terror, (for the devils believe and tremble,) or he made it with a design to render the character of Christ suspected. Possibly it was from hence the Pharisees took occasion to say, He casteth out devils by the prince of the devils.

Let...: or, Away

4:31-44 Christ's preaching much affected the people; and a working power went with it to the consciences of men. These miracles showed Christ to be a controller and conqueror of Satan, a healer of diseases. Where Christ gives a new life, in recovery from sickness, it should be a new life, spent more than ever in his service, to his glory. Our business should be to spread abroad Christ's fame in every place, to beseech him in behalf of those diseased in body or mind, and to use our influence in bringing sinners to him, that his hands may be laid upon them for their healing. He cast the devils out of many who were possessed. We were not sent into this world to live to ourselves only, but to glorify God, and to do good in our generation. The people sought him, and came unto him. A desert is no desert, if we are with Christ there. He will continue with us, by his word and Spirit, and extend the same blessings to other nations, till, throughout the earth, the servants and worshippers of Satan are brought to acknowledge him as the Christ, the Son of God, and to find redemption through his blood, even the forgiveness of sins.