On another question, Mike Bull suggests that there is a link between the five fold structure of the Psalms and that of Torah. I know he is not the only one to have suggested this before, but I'm curious on what basis (besides the number five) these two works are linked? Are there verbal and/or thematic connections between each of the books of Psalms and the Pentateuch?
The hypothesis of a link between the Five Books of the Psalmer and the Five Books of Moses is not a novel one. It dates back to even some of the earliest interpreters:
The ancient rabbins saw in the Five Books of the Psalter the image of the Five Books of the Law. This way of looking on the Psalms as a second Pentateuch, the echo of the first, passed over from the rabbins into the Christian Church and found favour with the early fathers.1
It's acceptance, however, is for many interpreters by no means assumed. For example, writing more recently Peter Craigie (WBC) states:
If the divisions were made first on the basis of the existence of the doxologies (which initially functioned internally within the psalms of which they are a part), then the analogy of the Five Books of Moses to the five so-called Books of Psalms may have suggested itself to the editor(s). But if such were the case, the correspondence does not go beyond the number five, and no firm internal correspondences or analogies can be established between the five Books of Psalms and the Five Books of Moses.2
Beyond the correspondence in number, however, others have noted a canonical reading of the Psalms which sees Psalm 1 (and 2) as an introduction to the greater work recommends to the reader the connection as well. Psalm 1 begins:
Blessed is the one...
whose delight is in the law of the Lord,
and who meditates on his law day and night.
The reader is thus invited to meditate on the law. But when read as an introduction to the Psalter as a whole, the opening verses seem to be an invitation to consider the Psalter in this way as well. It that sense, Psalm 1 recommends the Psalter as a second torah. This interpretation has a long heritage as well. Commenting on Psalm 1, the Talmud3 states: “Moses gave Israel the five books, and David gave Israel the five books of the Psalms.”
Beyond this, however, I must agree with Craigie that there is little firm ground for internal verbal or thematic correspondences. Many draw their own conclusions concerning any such correspondences; but no one theory seems yet to have won the day.
1 Binnie, W. (1886). The Psalms: Their History, Teachings, and Use (p. 116). London: Hodder and Stoughton.
2 Craigie, P. C. (2004). Psalms 1–50 (2nd ed., Vol. 19, p. 31). Nashville, TN: Nelson Reference & Electronic.
3 Midrash Tehillim