Luke 9:23 says:
"Then he said to them all: “Whoever wants to be my disciple must deny themselves and take up their cross daily and follow me." - Luke 9:23
Denying yourself is an essential part of the Christian life. Jesus called upon those who wish to be His followers to reject the natural human inclination toward selfishness. Self-denial for the Christian means renouncing oneself as the center of existence (which goes against the natural inclination of the human will) and recognizing Jesus Christ as one’s new and true center. It means acknowledging that the old self is dead and the new life is now hidden with Christ in God (Colossians 3:3–5).
When you are willing to sacrifice your time, energy, rights, position, reputation, privileges, comforts, and even your very life for the sake of Christ, you exemplify what it means to deny yourself:
“Whoever finds their life will lose it, and whoever loses their life for my sake will find it.” - Matthew 10:39