How do we know the importance of self-denial in Christianity?

Self-denial is emphasized throughout Scripture as essential for genuine discipleship. In Mark 8:35, Jesus declares that whosoever wishes to save their life will lose it, reinforcing the idea that true life is found in submission to Him rather than in clinging to worldly desires. This self-denial symbolizes a heart turned towards God and away from self-serving ambitions. It reflects the believer's understanding that worldly gains are temporary and cannot compare to the eternal value of the soul.