AMOUR OF THE MOST HIGH.

And Saul armed David with his armour, and David said unto Saul, I cannot go with these.......
King Saul had the honour of being the Israel's first king. As for David, he was just a shepherd boy.
While Saul by virtue of his sovereignty, Was The commander in chief of Israel's army.
David was not only a visitor to the battle front. The king was hiding somewhere far from the theatre of war but here was kiting up an ordinary lad in his personal armour to lead the battle he wouldn't fight. David appear inside the invisible armour of God which is beyond human understanding.