As always it depends on the translation you use whether the first word of the first Psalm is blessed or happy. Either way it seems significant to me that a worship song book begins in this way. The NRSV has “Happy are those who do not follow the advice of the wicked.” which is not so poetic as Coverdale’s “Blessed is the man that hath not walked in the counsel of the ungodly” but I would like to keep hold of the word “happy” as we look more closely at this piece. The Psalm contrasts the Godly in its first half with the ungodly in the second. Notice that the beginning talks about not walking in the counsel of the ungodly nor standing in the way of sinners. This is not about the unhappiness of sinning (this comes later) but about avoiding the lure of the siren voices, it is saying something about not exposing ourselves to the word or images of temptation. Rather, as verse two goes on to say, instead we should take delight in the law of the Lord and in meditating or musing on it day and night. Some translations use the term Torah of the Lord and this is helpful in directing our thoughts for we know the Torah was seen as guidance from the creator on the meaning of creation; it was to be studied and the point made is that life is lived fully if we can discover its meaning. Important then that this is told us in the first Psalm; it is like a preface to a modern book it is telling us why we should read on, why we should read the Psalter. Verse three explains that we who do read the Psalms, we who study God’s word shall be like a tree transplanted to flowing and healthful streams, we will flourish and our leaves will not wither an image of constant freshness. This is not eschatalogical, the Psalm is not speaking of the eternal promise of heaven and the after life but of now: this healthy, happy and hopeful state is now, it is a result of our meditating not a distant reward to be waited for. Happy is the man who reads the Psalms.
By contrast in verse five we see that this shall not be so for the ungodly who seek not deep understanding but temporal things. The winnower throws the scythed wheat into the air and while the heavier grain falls to the ground the lighter frivolous chaff flies away in the wind. The image not only forecasts the impermanence of the ways of the wicked but underlines the lightness and the scanty substance of these things. Again this is not about the afterlife, although it may apply. The way of the ungodly shall perish not as a punishment but as a result.
Now I am sure that this evening I am preaching to the choir, that you have worked out the truer values the things that make you happy such as praying, coming to church being generous and kind, taking lessons from God’s creation and a long list of others but to remind you this is Psalm one. This is all important for here at the beginning of the Psalter is a sort of evangelism that exhorts us not to be swerved by the words of the wicked, not to be scornful, not even to place ourselves within earshot of the temptation but by doing the right things to be delighted and happy - here and now. Think of that, not scripture that some see as saying follow these rules of denial and you will be blessed and the same scoffers say “can you be sure?” but a message that says this is the way and if you follow it you will discover blessing and happiness in your lives,. This is a message we should take joy in sharing with those who seem not to have discovered it yet.