Psalm 1

1 Blessed is the man
that walketh not in the counsel of the ungodly
nor standeth in the way of sinners,
nor sitteth in the seat of the scornful,
2 but his delight is in the law of the LORD,
and in his law doth he meditate day and night.
3 And he shall be like a tree planted by the rivers of water,
that bringeth forth his fruit in his season
his leaf also shall not wither;
and whatever he doeth shall prosper.

4 The ungodly are not so:
But are like the chaff
which the wind driveth away.
5 Therefore the ungodly shall not stand in the judgment,
nor sinners in the congregation of the righteous.

6 For the LORD knoweth the way of the righteous;
but the way of the ungodly shall perish.

JW: This psalm was put first as a preface to all the rest, as a powerful persuasive to the serious study of the whole book, and of the rest of the holy scripture, taken from that blessedness which attends upon the study and practice of it. It shews us: the holiness and happiness of a good man, ver. 1-3; the sinfulness and misery of a wicked man, ver. 4, 5; the ground and reason of both, ver. 6...

[On verse 1:] Observe a gradation in this verse; the following clause still exceeding the former, for standing is more than walking, and sitting more than standing; and sinners, in scripture use, are worse than the ungodly, and the scornful are the worst of sinners...

[On verse 3:] His happiness is not short and transitory, but like those trees which are continually green and flourishing.

I noticed the "gradation" of verse 1 and recall portions of the lecture by Dr. Owen Dickens in my undergraduate course in Psalms. Dr. Dickens gave us a visual picture of the progression from walking to standing to sitting. One might think that the deeper people get into a thing, the more active they become, but this is not the analogy given for abiding in wickedness. There is a progression toward what Wesley called "a more settled abode." The deeper we get into sinfulness, the more inactive we become. It's because it's the path that leads to destruction (v. 6) and death, which is the ultimate picture of inactivity. This progression should be opposite in the way of holy living! For more we abide in Christ, the more active we are. Think about the passages of discipleship: take up your cross and follow, walk in step with the Spirit, cast aside every weight and the sin that so easily ensnares and run with perseverance the race that is set before you.

"Delight" and meditate in the great commandment(s), which Jesus sees as the center of the law: "Love the Lord your God, with all your heart, mind, soul, and strength...and your neighbor as yourself." The phrase "day and night" is not just a suggestion to do devotions when you wake up and when you go to bed (though those are certainly good practices), but is an example of the poetical use of merism, whereby two contrasting parts (in this case "day" and "night") are highlighted to express the totality that lies in them and between them. In other words, we should meditate on the "law of the LORD" all the time. It's the following of the great commandments all the time.

"Prosper" sounds good. We need to be careful what sort of prosperity we're looking for. Where is your treasure? That's a good place to start when thinking of a biblical understanding of prosperity.

On verse 5 and the "nor sinners in the congregation of the righteous": I can easily imagine that this has been oft misconstrued into communicating that the "congregation" is only for saints. That's not the point. First, we need to remember who the Judge is. Second, we should remember that "all have sinned" and that includes me and you. Finally, it may do us some good to consider "the judgment" here to infer the final judgment, which Wesley did. The final judgment is yet to come. Accordingly, this isn't as much a passage of congregational living in the now, but a picture of what the eternal congregation in the new heaven and new earth will look like. In the meantime, let's take this Psalm as an encouragement to walk in the paths of righteousness, which includes encouraging others to do the same.