Because a Soldier that does not know his weapon, is a target.

Psalm 61

1 Hear my cry, O God; attend unto my prayer.

² From the end of the earth will I cry unto thee, when my heart is overwhelmed: lead me to the rock that is higher than I.

³ For thou hast been a shelter for me, and a strong tower from the enemy.

⁴ I will abide in thy tabernacle for ever: I will trust in the covert of thy wings. Selah.

⁵ For thou, O God, hast heard my vows: thou hast given me the heritage of those that fear thy name.

⁶ Thou wilt prolong the king's life: and his years as many generations.

⁷ He shall abide before God for ever: O prepare mercy and truth, which may preserve him.

⁸ So will I sing praise unto thy name for ever, that I may daily perform my vows.