TT #109 · Parashas Shoftim · Second Aliyah · Passuk 17:19
And it shall be with him, and he shall read in it all the days of his life, so that he may learn to fear the Eternal his God, to keep all the words of this Torah and these statutes, to do them.
Torah Temimah points to Sanhedrin 21b–22a.
TT lemma: וְהָיְתָה עִמּוֹ.
English: ‘And it shall be with him’ – that it shall be with him at all times, and in time of war it shall be with him.
Derash on constant presence (Bavli) — the scroll is not merely a library volume; it is a personal companion of the king.
The king’s Sefer Torah must remain with him at all times, including during war, so that he is never without the words of Torah.