What does Psalm 33:16 mean?

Although David had a strong army, he realized that earthly power does not guarantee victory. He applied the same awareness to individuals. A strong warrior cannot put absolute, infallible trust in his abilities. Goliath was an intimidating Philistine warrior, yet all his might could not prevail against young David, whose trust was in the Lord (1 Samuel 17:45–51). Believers can be certain they are on the side of victory with the Lord as their champion.

Gideon relied on the Lord for victory over the massive army from Midian. He was left with only three hundred men (Judges 7:5–7) against the Midianites who greatly outnumbered them (Judges 7:12). When Gideon and his men blew their trumpets and broke their jars with torches in them, they cried out, "A sword for the LORD and for Gideon!" (Judges 7:20). The Midian army panicked, fought among its ranks, and fled.

Trusting in the Lord and knowing He was present, Elisha chose not to be afraid of Syrian horses and chariots, or the huge army surrounding Dothan, where he was staying. Because his servant feared, Elisha asked the Lord to open his eyes so he would see. When the servant opened his eyes, he saw the mountain was full of horses and chariots of fire all around Elisha. Then, answering Elisha's second prayer, the Lord struck the Syrians with blindness (2 Kings 6:11–18).