It is one of the fruits of the mind (Galatians 5:22) that gives the ability to control one's emotions, thoughts, and behavior against temptations and impulses to achieve specific goals.
"Providing on your side any sustained effort, add to your faith the virtue, to your virtue the knowledge, to your knowledge the self-control."
Peter 1: 5, 6
A fruit that can be harvested by the crucifixion of the flesh that frees us from slavery, leading a new life under the dictation of the Holy Spirit. It has been given to us by Jesus Christ our Savior so that He may be glorified in us and by us.
Let's practice self-mastery in order to reach our greatest goal in life which is to please God and not to impress people!