מלכים ב ט:א פירוש: רש״י

Elisha the prophet called, etc. At the same time that Yehorom was ill in Yizre’el.

One of the prophets’ disciples. It was Yonah son of Amitai.

“Gird you loins.” Every “girding of the loins” is an expression of hurry¹See above 4:29, and Shemos 12:11. [and] might; because he was sent on a perilous mission (he needed to hurry).²Even though one who performs a mitzvah is ordinarily immune from any harm befalling him, this does not apply to exceptionally dangerous activities such as this. See Maseches Chulin 142a.