Spell Scrolls were used in the past as a way to learn spells. Back then, paladins could buy a Summon Creature Spell scroll and use it when the said paladin advanced to magic level 16.
Spell Scrolls are not sold anymore, however some characters that learned spells exclusive to other vocations from spell scrolls existed until Update 10.55 when vocation requirement was also applied while casting spells, not just while buying them.
Spell Scroll for Energy Wall Rune.