Psalms 49:18 (KJV) says, "Though while he lived he blessed his soul: and men will praise thee, when thou doest well to thyself."

In order to understand the full meaning and context of this verse, it is important to examine the entire chapter of Psalms 49. This chapter is often referred to as a wisdom psalm, as it offers valuable insights into the true worth of wealth and material possessions in comparison to the value of wisdom and understanding. The psalmist begins by declaring that he will speak wisdom and understanding, and he calls on all people, both high and low, rich and poor, to listen to his words. He emphasizes that his teachings come from a deep understanding of the truths of God and the world.

The verse in question, Psalms 49:18, comes towards the end of the chapter and seems to be emphasizing the fleeting nature of material wealth and the foolishness of trusting in one's own accomplishments. The psalmist refers to a person who "blessed his soul" while he lived, meaning that he lived to satisfy his own desires and lived for himself. This person may have been rich and successful, and received praise from others for his accomplishments. However, the psalmist implies that this praise is superficial and meaningless in the grand scheme of things.

The phrase "when thou doest well to thyself" can be interpreted in different ways. It could mean that the person received praise and admiration from others when he fulfilled his own desires and pursued his own interests. However, it could also mean that true praise and worth come from living a righteous and wise life. When someone acts in a way that is truly beneficial for their soul and for others, that is when they will receive true praise and admiration.

The themes present in this verse and the chapter as a whole revolve around the idea of the true worth of material wealth, the fleeting nature of earthly accomplishments, and the value of living a life of wisdom and understanding. Throughout the chapter, the psalmist contrasts the fate of the rich and the poor, emphasizing that ultimately, all people will die and leave their wealth behind. No amount of riches can buy a person's way out of death, and in the grand scheme of eternity, material possessions and accomplishments are insignificant.

Symbolically, the act of "blessing his soul" while living can be seen as a self-centered and selfish pursuit of one's own desires and interests. In contrast, "doing well to thyself" can be viewed as acting in a way that is truly beneficial and fulfilling for one's soul. This can be seen as living a life of righteousness, wisdom, and understanding, rather than living for material gain and fleeting accomplishments.

Overall, Psalms 49:18 serves as a reminder that true worth and praise come from living a life of wisdom, understanding, and righteousness, rather than from pursuing wealth and self-centered desires. It encourages readers to seek a deeper understanding of the true value of life and the fleeting nature of material possessions. The verse also serves as a call to live in a way that is truly beneficial for one's soul, and in turn, receive praise and admiration for living a life of wisdom and righteousness.