Psalm 58:10 is a powerful and often disturbing verse. To understand it, it's important to consider the historical context, the genre of the Psalms (specifically, imprecatory psalms), and different interpretations.

Here's a breakdown:

"The righteous shall rejoice when he sees the vengeance." This part refers to the joy the righteous will feel when they witness God's justice being carried out on the wicked. This doesn't necessarily imply a personal desire for revenge but rather a sense of vindication when wickedness is punished and righteousness is upheld. It's about justice being served and the establishment of God's order.

"He shall wash his feet in the blood of the wicked." This is the most graphic and controversial part. It's a metaphorical expression, not a literal instruction. It is hyperbolic imagery, using exaggeration to make a strong point. Possible interpretations include:
Complete and Utter Victory: The image suggests a decisive and overwhelming victory over the wicked. The blood symbolizes their defeat and the thoroughness of the victory. Just as someone might wash their feet after walking through a bloody battlefield, the righteous are depicted as being completely untouched by the wickedness they have overcome.
Symbolic Cleansing: The washing of feet can also symbolize purification or cleansing. The righteous are cleansed and vindicated by the removal of wickedness from their midst.
Humiliation of the Wicked: The image might represent the utter humiliation and degradation of the wicked. Their defeat is so complete that their blood becomes like common dirt, something to be washed off the feet.
Theological Interpretation: It's crucial to remember this is a poetic expression of faith in God's justice. It's not necessarily a literal call to violence but a statement of confidence that God will ultimately right all wrongs.

Key Considerations:

Imprecatory Psalms: Psalm 58 belongs to a genre known as "imprecatory psalms," which are prayers calling for God's judgment on enemies. These psalms reflect the intense emotions of those suffering injustice and their longing for God to intervene. It's important to remember that these psalms express human emotions, not necessarily a divine command.
Historical Context: The psalm was likely written during a time of great oppression and injustice. The writer is crying out for God to deliver them from the wicked.
Figurative Language: The verse uses highly figurative language. It's important to interpret it within the context of Hebrew poetry and its use of symbolism and metaphor.
Moral Dilemma: Many find the imagery in this verse troubling, as it seems to condone violence and even relish in the suffering of others. However, interpreters often emphasize that the verse is about the triumph of justice and the vindication of the righteous, not about personal revenge. It's also vital to place it within the context of the Old Testament's legal and ethical frameworks, which were different from New Testament teachings.

Interpretational Challenges and Modern Relevance:

This verse raises important questions about justice, vengeance, and the role of violence in faith. Modern readers often struggle with the seemingly vengeful tone of imprecatory psalms. Some theologians argue that these psalms reflect the limited understanding of justice in the Old Testament and are superseded by the teachings of Jesus on love, forgiveness, and turning the other cheek.

However, others argue that these psalms still have value in expressing the pain and anger of those who have been wronged and in affirming the importance of justice. They also remind us that God is ultimately responsible for judging the wicked.

Ultimately, Psalm 58:10 is a complex verse that requires careful interpretation. It is a powerful expression of faith in God's justice, but it also raises important questions about the relationship between justice, vengeance, and love.