Secure in the salvation that only God can give, the writer-monarch who penned Psalm 21 crows about the things the Lord has done, especially for him. Obviously, he realises he has a lot to be grateful for. He can point to answered prayers, inner fulfillment, a flourishing kingdom, life more abundant, a growing reputation among the kings of the world, the remembrance of God and joy unadulterated.
Perhaps to encourage others, this totally fulfilled writer surprisingly volunteers to state the factor he believes is responsible for his present state - his trust in the Lord, which is rock solid. He believes that as he continues to trust God he remains impregnable and nothing can touch him or bring him down.
Garrisoned in the faith that he reposes in God, the writer is so confident that he even pronounces victory before it is won. He states that at the end of it all both he and his people would still be standing and praising the Lord. Amazingly, he is so subsumed in God that he no longer recognises his enemies as his. As far as he is concerned, his enemies are now God's enemies, and so the confrontation is between them and God. Therefore, like someone who is privy to the secrets of God, he spells out what the Almighty will do to the enemies. In a prophetic effusion, he not only describes in detail the fate of the enemies but also what would become of their allies and their descendants who would be destroyed. As he gingerly removes himself from the firing line, hiding behind God, this writer-king reminds the Almighty of what these enemies had intended to do. Therefore, his stand was that as these enemies are not particularly merciful there is no reason why they should be shown any.