Warrior Kneels Over Fallen Enemies by City Wallsby CBPepper

Psalms 18:40

Thou hast also given me the necks of mine enemies; that I might destroy them that hate me.

It is part of David's triumphant song celebrating marvelous deliverance from enemies on the field of victory.
It is David's thanksgiving for being delivered from the hand of Saul.
The same psalm is recorded in 2 Samuel 22, where its historical connection is shown, while Psalm 18 presents it as part of the collection of David's writings, and the two chapters parallel each other closely but are not exactly alike.
It means that God gives victory by making enemies submit, so that those who hate may be brought down, and David credits God rather than himself for the victory.

It shows mistrust of human strength and exaltation of divine power, expressing confidence in God's might and goodness and assurance that all wickedness will finally be overthrown and all good will triumph.
It belongs to a prophetic picture of Christ's life-and-death struggles with the enemy, portraying conflict and triumph, without further specification of its individual meaning.
In connection with Christ, the psalm is about resurrection, in which he was lifted up and his foes were not allowed to rejoice over him.
It reflects something of the experience of Christ as the greater Son of David.

It points to Christ's victory on behalf of believers and within them over sin and spiritual foes.
Though part of the Old Testament given to the Jews as God's people in that dispensation, its moral principles also concern Christians as God's people now, for the whole Bible reveals to fallen humanity the plan of redemption and resulting duty, so every part is to be learned for that duty, just as letters addressed to the Romans, Corinthians, Galatians, Ephesians, Philippians, Colossians, Thessalonians, Hebrews, scattered strangers, and the seven churches in Asia concern all Christians and not only those directly addressed.
It is instructive, devout, helpful, elevating and worshipful, teaching trust and confidence in God.