How does this ending particle じ work?


I've seen this particle used before multiple times but have chosen to ignore
it each time. Though here's an example where I can find this particle being
used.

冬来りなば春遠からじ - (from what I guess it might mean, "When winter comes, spring
can't be that far behind")




It is an archaic auxiliary verb
[じ](https://dictionary.goo.ne.jp/word/%E3%81%98/#jn-92527).

It means _will not_. Thus 春遠からじ means _spring won't be far_.

* * *

In modern usage, it appears mostly in fixed expressions like 負けじと.

