That Heaven would want spectators, God want praise:
'Want' means 'lack' here, as in "The garden wants water - The garden lacks water".
Don't think that, even though there are no people here, heaven lacks spectators or God lacks praise.
"Millions of spiritual creatures walk the earth ...
All these with ceaseless praise his works behold
Both day and night"
Heaven and God don't lack praise because millions of creatures, even if not people, are ceaselessly praising God's works.
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