Psalms 104:33 - Albert Barnes' Notes on the Bible

I will sing unto the Lord as long as I live - That is, I will continue to praise him; I will never cease to adore him. The result of the psalmist’s meditations on the wonderful works of God is to awaken in his mind a desire to praise God forever. He is so filled with a sense of his greatness and glory that he sees that there would be occasion for eternal praise; or that the reason for praise could never be exhausted. He who has any proper sense of the greatness, the majesty, and the glory of God “intends” to praise him forever. He sees that there is enough in the character of God to demand eternal praise, and he does not anticipate that a period can ever occur in all the future when he will feel that the causes for praise have come to an end, or when his heart will be indisposed to celebrate that praise.