What does the Bible say about the vanity of life without Christ?

Throughout Ecclesiastes, Solomon emphasizes the worthlessness of life without a relationship with God, particularly as revealed through Christ. In Ecclesiastes 12, he presents the idea that no matter the pleasures or successes a person achieves in life, if they are devoid of God's grace and truth, their existence will amount to vanity. This perspective highlights the essential nature of Christ; without Him, even the best of life leads to death and judgment. The implication is that a true understanding and acceptance of Christ's work is paramount to meaningful existence and eternal hope.