Count the commands in Psalm 100 and you get seven: shout, serve, come, know, come, give thanks, bless. In a psalm this short — five verses — that is a remarkable density of imperatives, and the number is almost certainly deliberate. In the Hebrew Bible, seven is the number of completeness, the count that runs from the seven days of creation onward whenever something is whole and lacking nothing.

So the seven commands may be doing more than piling up enthusiasm. Laid out, they quietly answer every question you could ask about worship. Whom do you praise? YHWH, the one supreme God. Where? In his presence, through his gates, into his courts. How? With joyful shouts, with service, with thanksgiving, with blessing. Why? Because you belong to him, and because he is good, and his love runs on forever. Who, whom, where, how, why — a complete picture, folded into five verses.

And every one of the seven is soaked in the same mood. Shout joyfully. Serve with gladness. Come with singing. Enter with thanksgiving. The psalm isn’t handing out obligations. Seven times over — the full and perfect number — it describes a kind of worship whose natural temperature is joy.

A complete account of how to praise God turns out to be, start to finish, an account of delight.

Read more on psalms.scriptura.org → Psalm 100 Poetry