Book Four of the Psalter begins with a progressive triplet – Psalms 90 through 92.
 Psalm 90:0 is characteristically ‘the prayer of the Moses generation’ who are referred to in twenty-four plural words (‘we’, ‘us’, ‘our’, ‘their’ and ‘servants’);
 Psalm 91:0 could well be labelled ‘the psalm of the Joshua generation’ with its thirty-five singular personal pronouns [King James Version has ‘thee’ and thou’]; and, since Joshua did not achieve sabbath rest for them (see Hebrews 4:8-10),
 Psalm 92:0 could be entitled ‘a song for the Sabbath generation’, in which the singer uses nine singular pronouns (‘my’), then morphs into a corporate identity using plural pronouns (Psalm 92:12-15, ‘they’ and ‘their’), yet ending with a personal ‘my’ (Psalm 92:15).
- Its caption: ‘A Prayer of Moses, the man of God’ – an accolade bestowed by pioneers: by Joshua (?) in Deuteronomy 33:1 at the end of the wilderness years; by Caleb at the end of the Conquest in claiming his promised inheritance (Joshua 14:6); and by Ezra (Ezra 3:2) to the generation of settlers after their exile in Babylon.
- Moses’ confession (Psalm 90:1-10)
After leading the exodus generation for forty years in ‘the great and terrifying desert’ (Deuteronomy 8:15), having been denied entry to the land for four decades, Moses had watched them dying at a mere seventy or eighty years! Appropriately, he compares:
- God’s eternal existence (Psalm 90:1-2) as ‘our refuge’ [Hebrew] in our homelessness (1; Psalm 71:1, same Hebrew word). In contrast, though the people of God endure as an entity like God ‘through all generations’, yet individually we are all proofs of
- human ephemeral existence (Psalm 90:3-10).
 ‘We are frail’ (Psalm 90:3-6). They were:
* dying in the desert (Psalm 90:3); * a mere night vigil (Psalm 90:4); * a wadi in the dry season (Psalm 90:5a); a brief, dream-filled snooze (Psalm 90:5b); * grass, dew-drenched then scorched (Psalm 90:5-6).
 ‘We are faulty’ (Psalm 90:7-10). In his ‘swan song’, Moses urged the Joshua generation: ‘Take to heart all the words by which I am warning you today…and by this word you will live long in the land’ (Deuteronomy 32:44-47). Therefore the Joshua generation confessed their hope of ‘long life’ at the end of their psalm (91:16).
- Moses’ petition (Psalm 90:11-17)
He asked the Lord for:
- your prudence in us (‘wisdom’, ‘to number our days’, Psalm 90:12);
- your presence with us (Psalm 90:13-17a) – the mercy (Psalm 90:13), the joy (Psalm 90:14-15), the display (Psalm 90:16, ‘by signs and wonders’, Hebrews 2:4), and the beauty (no’am, Psalm 90:17a) of the Lord;
- your permanence through us (the durability of our work despite our brevity of life, 17b-c). ‘Be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord your labour is not in vain’ (1 Corinthians 15:58; compare Revelation 14:12-13, ‘the dead who die in the Lord…rest from their labours, for their deeds follow them’).