וַיֵּצֵא֩ סִיחֹ֨ן לִקְרָאתֵ֜נוּ ה֧וּא וְכָל־עַמּ֛וֹ לַמִּלְחָמָ֖ה יָֽהְצָה׃
איז סיחין אַרױסגעגאַנגען אַקעגן אונדז, ער מיט זײַן גאַנצן פֿאָלק, אױף מלחמה קײן יַהַץ.
Rashi
ויצא סיחן AND SIHON WENT FORTH — He did not send for Og to help him: this serves to teach you that they did not require one another's help, so mighty was each of them.
Siftei Chakhamim
He did not send for Og, etc. Because they were powerful.