Ephesians 6:12 For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.
[Patriarchs & Prophets pp 690] David and his men had not taken part in the battle between Saul and the Philistines, though they had marched with the Philistines to the field of conflict. As the two armies prepared to join battle the son of Jesse found himself in a situation of great perplexity. It was expected that he would fight for the Philistines. Should he in the engagement quit the post assigned him and retire from the field, he would not only brand himself with cowardice, but with ingratitude and treachery to Achish, who had protected him and confided in him.
Such an act would cover his name with infamy, and would expose him to the wrath of enemies more to be feared than Saul. Yet he could not for a moment consent to fight against Israel. Should he do this, he would become a traitor to his country—the enemy of God and of His people. It would forever bar his way to the throne of Israel; and should Saul be slain in the engagement, his death would be charged upon David. David was caused to feel that he had missed his path.
Far better would it have been for him to find refuge in God's strong fortresses of the mountains than with the avowed enemies of Jehovah and His people. But the Lord in His great mercy did not punish this error of His servant by leaving him to himself in his distress and perplexity; for though David, losing his grasp on divine power, had faltered and turned aside from the path of strict integrity, it was still the purpose of his heart to be true to God.
Ephesians 6:13 Wherefore take unto you the whole armor of God, that ye may be able to withstand in the evil day, and having done all, to stand.
May The Lord add His blessing to the study of His word. God bless!