The last we heard from Terence Blanchard on record was the vibrant Flow, which he showcased at the 2005 Essence Festival as the marquee New Orleans act on the bill. That recording’s soothing grooves were inspired by Mihaly Csikszentmihalyi’s book Flow: the Psychology of Optimum Experience. Little did Blanchard know that by the end of the summer, the experience he was destined to live through was watching his hometown swallowed up by Lake Ponchartrain, a deluge that nearly killed his mother. Spike Lee’s documentary When the Levees Broke turned Blanchard’s mother into a touchstone for the tens of thousands whose lives were completely upended by the flood, and Blanchard ended up with the task of translating that grief to music. It’s hard to imagine a more difficult job, but Blanchard will never be accused again of neglecting his roots in pursuit of Hollywood Dreams.

A Tale of God’s Will is an expansion of the music Blanchard and his band made for the Lee documentary, and it moves with the epic scope of the flood itself. Blanchard, bassist Derrick Hodge and Aaron Parks on piano all turn in great performances. With as much orchestration as the Northwest Sinfonia add to the mix, an extra weight of responsibility falls on the instrumentalists to represent point-of-view. Hodges’ frenetic bass work on the opening track “Tales of Congo Square” moves with the lateral motion of a broken field runner, meshing expertly with Kendrick Scott’s percussion to establish the project’s mood. Exposition begins immediately with “Levees,” an orchestral piece that evokes an awesome beauty as Blanchard’s expressive trumpet floats over the hypnotic ebb and swell. That narcotic-like feeling of being slowly overwhelmed evokes those who stayed behind through “Levees” and witnessed the slow, languishing horror of “Wading Through,” which rides on a simple, poignant exposition of the theme by Parks.

Though Blanchard composed and orchestrated much of the recording, other members of his group contributed. Reedman Brice Winston composed “In Time of Need,” an introspective theme that allows him to explore his roots in the questing balladry of John Coltrane and features an outstanding Blanchard trumpet solo. Hodge wrote the widescreen vision of “Over There,” which recapitulates the “Levees” theme, and Scott the extravagantly scored “Mantra” suite, which utilizes Zack Harmon’s tablas effectively. Parks matched the delicacy of his playing with the eerily beautiful “Ashe.”

Blanchard has devoted the bulk of his career to scoring films, becoming an Ennio Morricone to Spike Lee’s Sergio Leone along the way, and his compositions, especially “Water” and “Funeral Dirge,” live up to their responsibilities as program music, the former in a Debussy-esque liquidity that is embodied in Blanchard’s tidal trumpet lines, the latter in appropriate New Orleans funeral procession tradition. Blanchard is fine with his themes fading in and out at the beginning and end of takes, a quirk which would be irritating on a conventional jazz album (“Ghosts of 1927” is a fragment of an interesting tenor solo) but makes reasonable sense in soundtrack music.

The album ends on Blanchard’s biggest challenge, “Dear Mom,” the moment where the impersonal task at hand meshes with the terror of personal experience. The string introduction is tearfully tender, setting up Blanchard’s plangent trumpet theme, layered softly over and over the orchestration. The piece is so powerful that despite its languorous cadence, it seems over much more quickly than its 3:40 timing, making it of a piece with a soundtrack that has such depth that even though most of it is elementally slow moving it manages to keep you on the edge of your seat throughout.