Psalm 145 is called "David's Psalm of praise," and you will see that all through it he is inflamed by a strong desire that God may be greatly magnified. Hence he uses a variety of expressions, and repeats himself in his holy vehemence. Run your eye down the psalm and notice such words as these: "I will extol thee"; "I will bless thy name"; "Every day will I bless thee"; "I will praise thy name forever and ever"; "Great is the Lord, and greatly to be praised"; "One generation shall praise thy works, to another"; "I will speak of the glorious' honor of thy majesty; "Men shall speak of the might of thy terrible acts," and other words of like import, down to the last verse': "My mouth shall speak the praise of the Lord: and let all flesh bless his holy name forever and ever."
David is not content with declaring that Jehovah is worthy of praise, or with pleading that his praise ought to be felt in the heart, but he will have it publicly spoken of, openly declared, plainly uttered, and joyfully proclaimed in song. The inspired Psalmist, moved by the Holy Ghost, calls upon all flesh, yea, and upon all the works of God to sound forth the praises of the Most High. Will we not heartily respond to the call?
Taken from the Book Spurgeon on Praise Charles Spurgeon 1834-1892