Acts 17:31

Because he hath appointed a day
The day of judgment is fixed by God in his eternal purposes, and is sure and certain, and will come, though it is not known by men or angels; and this is a reason why God will have the doctrine of repentance everywhere published, both to Jews and Gentiles, since all must come to judgment: and the day for it is appointed by him,

in the which he will judge the world in righteousness;
the whole world will be judged, and every individual in it, good and bad, righteous and wicked; and this judgment will be a righteous one; it will proceed according to the strict rules of justice and equity, and upon the foot of the righteousness of Christ, as that has been received or rejected by men, or as men are clothed with, or are without that righteousness:

by that man whom he hath ordained;
Beza's ancient copy reads, "the man Jesus": not that the apostle means that Christ is a mere man; for then he would not be fit to be a Judge of quick and dead, and to pass and execute the definitive sentence; which requires omniscience and omnipotence: but preaching to mere Heathens, he chose not at once to assert the deity of Christ, though he tacitly suggests it: but intended, by degrees, to open the glories of his nature and office to them, he being the person God had from all eternity ordained, and in time had signified, should have all judgment committed to him, and by whom the last judgment shall be managed and transacted:

whereof he hath given assurance to all men:
or full proof, both of his being the Judge, and of his fitness to be one, and also of the righteousness, according to which he will judge:

in that he hath raised him from the dead;
whereby he was declared to be the Son of God; and when all power in heaven and in earth was given to him; and which was done for the justification of all those for whose offences he was delivered: and this seems to be the reason why the apostle calls Christ the Judge a man, that he might have the opportunity of mentioning his resurrection from the dead.