How do we know the importance of the soul in Christian theology?

In Mark 8:36-37, Jesus raises the poignant question, 'What shall it profit a man if he shall gain the whole world, and lose his own soul?' This emphasizes the unspeakable value of the soul, which will endure beyond earthly existence. The text warns against the foolishness of prioritizing transient worldly gain over eternal salvation. As believers, we must recognize that neglecting the care of our souls can lead to spiritual ruin. Our focus should not be on temporal pleasures but on the eternal significance of our souls, leading us to understand how critical it is to seek salvation through Christ, who is the sole redeemer of our souls.