O LORD, in your strength the king rejoices, and in your salvation how greatly he exults!  You have given him his heart’s desire and have not withheld the request of his lips. Selah  For you meet him with rich blessings; you set a crown of fine gold upon his head.  He asked life of you; you gave it to him, length of days forever and ever.  His glory is great through your salvation; splendor and majesty you bestow on him.  For you make him most blessed forever; you make him glad with the joy of your presence.  For the king trusts in the LORD, and through the steadfast love of the Most High he shall not be moved.  Your hand will find out all your enemies; your right hand will find out those who hate you.  You will make them as a blazing oven when you appear. The LORD will swallow them up in his wrath, and fire will consume them.  You will destroy their descendants from the earth, and their offspring from among the children of man.  Though they plan evil against you, though they devise mischief, they will not succeed.  For you will put them to flight; you will aim at their faces with your bows.  Be exalted, O LORD, in your strength! We will sing and praise your power. (Psalm 21 ESV)
The Lord is a Ferocious Warrior
The Lord defeats his enemies in a ferocious display of strength and wrath (8-9). This is a familiar idea:
Therefore, a curse devours the earth, and its inhabitants suffer for their guilt; therefore the inhabitants of the earth are scorched, and few men are left. (Isaiah 24:6)
For behold, the day is coming, burning like an oven, when all the arrogant and all evildoers will be stubble. The day that is coming shall set them ablaze, says the Lord of hosts, so that it will leave them neither root nor branch. (Malachi 4:1)
God still will defeat his enemies. The day is still approaching when he will put all of his enemies down and his glory will be emblazoned into the sky from the fire of his justice (Matthew 25:41; Revelation 20:14).
Not only that, those who oppose the Lord will fail in their campaign against him. This is the ultimate in futile effort.
No wisdom, no understanding, no counsel can avail against the Lord. (Proverbs 21:30)
That certainly was the case with the Pharisees. They plotted and schemed to kill Jesus and in their plotting and scheming, they worked into the plans of the Almighty Sovereign over the universe and were a part of the provision of salvation for all who believe. In their condemnation, we find forgiveness from condemnation (Romans 8:1).