The Lord shall laugh at him - See the notes at Psalm 2:4. That is, he will regard all his attempts as vain - as not worthy of serious thought or care. The language is that which we use when there is no fear or apprehension felt. It is not that God is unfeeling, or that he is disposed to deride man, but that he regards all such efforts as vain, and as not demanding notice on the ground of anything to be apprehended from them.
For he seeth that his day is coming - The day of his destruction or overthrow. He sees that the wicked man cannot be ultimately successful, but that destruction is coming upon him. There is nothing ultimately to be apprehended from his designs, for his overthrow is certain.

He seeth that his day is coming - The utter desolation of your oppressors is at hand. All this may be said of every wicked man.

The Lord shall laugh at him,.... Have him and his plots in derision, confound his schemes, and disappoint him of his designs, bring him into calamity, and laugh at it; see Psalm 2:4;
for he seeth that his day is coming; either the day of the Lord, which he has appointed to judge the world in, and which comes suddenly, at unawares, as a thief in the night, and is known unto the Lord, though to none else; or the day of the wicked man's ruin and destruction, to which he is appointed, and which is the same; and so the Targum is, "the day of his calamity": which the Lord observes is hastening on, when he will be for ever miserable.

(Compare Psalm 2:4).
seeth--knows certainly.
his day--of punishment, long delayed, shall yet come (Hebrews 10:37).

His day - The day appointed by God for his punishment or destruction.