Thought from Today’s Old Testament Passage:
[Psalm 150] This psalm, which concludes the book and all the Psalter as final doxology, is the most comprehensive and illuminative illustration of perfect praise in the whole Psalter.
The central place of prayer is the sanctuary, that is, the place of divine manifestation, whether the earthly temple or the heavenly matters nothing. The circumference is the firmament of His power, which is the outer confine of human consciousness.
The reason for praise is His mighty acts, whether in creation, redemption, or government. The measure of praise is His excellent greatness, so that it can never end until all the story be exhausted. The method is set forth by a description of the instruments of music constituting a perfect orchestra.
Finally, the one condition of praise is the possession of breath, that is to say, life received from Him must return in praise to Him. The function of life is praise, and the force of praise is life. The note of responsibility and the dignity of choice are alike indicated in the fact that the final psalm is not merely an expression of praise but a call to its exercise. Thus it is seen that the worship which perfectly glorifies God is not mechanical but volitional.
G. Campbell Morgan, An Exposition of the Whole Bible (Fleming H. Revell Co., 1959), pp. 277-78.