en_tn/mrk/03/26.md

If Satan has risen up against himself and is divided

The word "himself" is a reflexive pronoun that refers back to Satan, and it is also a metonym for his evil spirits. Alternate translation: "If Satan and his evil spirits were fighting one another" or "If Satan and his evil spirits have risen up against each other and are divided" (See: rc://en/ta/man/jit/figs-rpronouns and rc://en/ta/man/jit/figs-metonymy)

is not able to stand

This is a metaphor meaning he will fall and cannot endure. Alternate translation: "will cease to be united" or "cannot endure and has come to an end" or "will fall and has come to an end" (See: rc://en/ta/man/jit/figs-metaphor)