Rabeinu Bachya, commentary to Exodus 35:2

"...Making fire is an appropriate example of basic human activity seeing that most of the principal activities we are engaged in cannot be performed satisfactorily if one were not able or allowed to make fire. This is the reason that the sages instituted the benediction over fire during the havdala ritual at the end of the Sabbath to signify that this crucial activity (as well as other activities) which was prohibited on the Sabbath is once again permitted. Fire, i.e. light, was the first of the activities G'd engaged in when creating the universe (Genesis 1:2).” [Translation and annotation by Eliyahu Munk]