[dungeonguru]

Are you sure you're not confusing slots available with number of spells memorized?

A cleric can only memorize a number of spells equal to their level plus their wisdom bonus. These spells can be any level for which they have appropriate level slots available. You also get the free memorized domain spells.

SO:
a 5th level cleric with a +2 wisdom bonus can memorize 7 spells.
they can cast those spells using the slots given for their level:
4x 1st level slots, 3x 2nd level, 2x 3rd level.

This means they can memorize 7 spells in any combination:
- all 7 1st level spells
- all 7 3rd level spells
- any 7 of spells 1st-3rd level

The slots are seperate - if you memorized all 7 spells available as 1st level you could cast 4x 1st level spells as 1st level, plus some of the spells as 2nd level - like casting Cure Wounds as 2nd level or 3rd level.

Note, some people think that the Domain spells can be cast for free - they are not - they require expending a spell slot just like any other.