The verse Psalms 73:21 from the King James Version of the Bible reads:

"Thus my heart was grieved, and I was pricked in my reins."

Psalms 73 is a psalm attributed to Asaph, who is described in the Bible as a Levite and a chief musician during the reign of King David. This particular psalm is a meditation on the apparent prosperity of the wicked and the resulting struggle of the righteous. The verse 21 comes in the middle of the psalm in which the psalmist expresses his inner turmoil over the seeming success and happiness of those who are not walking in righteousness.

The phrase "Thus my heart was grieved, and I was pricked in my reins" provides a glimpse into the internal struggle of the psalmist. The word "reins" is an old word for the inward parts of the body, often associated with the seat of emotion or feeling. In this verse, the psalmist is expressing how deeply he was affected by the prosperity of the wicked. His heart is full of sorrow and pain at the sight of their seemingly carefree existence.

The context of this verse is important for understanding its deeper meaning. The psalmist begins by acknowledging the struggle he has faced in keeping his faith in God in the face of the prosperity of the wicked. He even admits to being envious of their success and wealth, feeling that his own righteousness has been in vain. However, as the psalm progresses, he comes to a realization that their prosperity is temporary and will ultimately lead to their downfall. This leads him to a place of greater trust and faith in God's justice and righteousness.

The theme of this verse can be seen as the struggle of faith in the midst of adversity. The psalmist is grappling with the age-old question of why the righteous suffer while the wicked prosper. This theme is one that resonates with many people, as it speaks to the universal experience of grappling with the injustices of the world. The theme of internal struggle is also prevalent in this verse, as the psalmist is dealing with the conflicting emotions of envy, grief, and doubt.

The symbolism in this verse can be found in the imagery of the heart being grieved and the reins being pricked. The heart is often symbolic of the innermost being, the place where emotions and desires reside. The psalmist's heart is burdened and filled with sorrow as he grapples with the unfairness of life. The "reins" being pricked can symbolize the psalmist's inner turmoil and the feeling of being prodded or poked by his emotions. This imagery serves as a powerful portrayal of the psalmist's inner struggle.

Overall, Psalms 73:21 is a verse that captures the deep emotional and spiritual battle of the psalmist as he wrestles with the apparent prosperity of the wicked. It speaks to the universal struggle of maintaining faith and trust in God in the face of adversity and injustice. The verse ultimately serves as a reminder of the temporary nature of earthly success and the ultimate justice and righteousness of God.