דברי הימים ב, פרק כ״ט, פסוק ל׳

A great gathering of praise orchestrated by the king and his leaders brought together ancient traditions of song and a profound spiritual awakening among the people. When the leaders instructed the Levites to offer praise to God, they directed them to use the historical words of David and Asaph the seer. There are different ways to understand exactly what they sang. A specific view suggests they chanted the exact psalm of thanksgiving, "Give thanks to God, call upon His name," which David had established long ago [רש״י]. A broader perspective understands this instruction as a general call to sing the various psalms and songs of gratitude authored by both David and Asaph [מצודת דוד, רלב״ג]. Asaph is notably called a seer because he served directly as David's visionary [רלב״ג], composing his music through the direct influence of divine inspiration [ביאור שטיינזלץ].

As the Levites sang, the music swelled and intensified until it brought about a profound state of joy. This emotional peak was achieved through the deep devotion to God that the singers experienced as they praised Him [מצודת דוד]. This intense joy quickly broke outward, sweeping through the entire gathered crowd [ביאור שטיינזלץ]. Moved by such overwhelming excitement and happiness, the people responded with physical acts of submission. First, they bent down and bowed their heads in reverence [מצודת ציון, ביאור שטיינזלץ]. Then, taking their devotion a step further, they prostrated themselves completely flat upon the ground [ביאור שטיינזלץ].