Blessed are they that keep judgment,.... Or "observe" it; the righteous judgment of God on wicked men; by which he is known in his justice, holiness, truth, and faithfulness; and by which the inhabitants of the earth observing it, learn to do righteousness, as follows: or else it may intend the word of God, his laws, statutes, and ordinances, after called his judgments, Ps 19:9, which should be observed and kept, as the rule of our actions, walk, and conversation.
[And] he that doeth righteousness at all times; continually believes in Christ for righteousness, and puts on that as his justifying righteousness; whereby he becomes righteous as he is, 1Jo 3:7, and performs acts of righteousness from a principle of grace, as a fruit of regeneration, and an evidence of it, 1Jo 2:29, that does it with right views, aims, and ends; not to be justified and saved by it, but because God requires it; and it is for his glory, and to testify subjection to him, and thankfulness for favours received from him.
And this is to be done at all times; we should never be weary of well doing, but be always abounding in good works; and happy are those that will be found so doing, such are "blessed" persons: not that their blessedness lies in or arises from righteousness done by them; but this is descriptive of such that are blessed in Christ with the remission of sins, and his justifying righteousness.
And these are the proper persons to show forth the mighty acts and praise of the Lord; they are most capable of it, and more likely to perform it with acceptance than any other; see Ps 50:14.