From Carl Stam’s Worship Quote of the Week:

How do we face troubles with peace, rest, and equilibrium? The ultimate
way to handle the troubles of life is not just through prayers of
petition, but through worship. . . . Worship is the act of ascribing
ultimate value to something in such a way that it engages the entire
being: mind, will, and emotions.

— Timothy J. Keller (Redeemer Presbyterian Church, New York City), from
a sermon on Psalm 95 and “biblical worship,” July 7, 2002.

Stam has also posted the audio of this online.  There are a number of excellent resources at the Institute for Christian Worship website.