Discipline is the ability to live by certain rules or guidelines in order to grow physically, mentally, or spiritually.
Let no one look down on your youth, but be an example to the believers in word, in behavior, in love, in spirit, in belief, in cleanliness. Until I come, give attention to reading of Scripture, to encouragement, to teaching. Do not neglect the gift that is in you, which was given to you by prophecy with the laying on of the hands of the elder hood. Practice these matters, be in them, so that your progress might be plain to all. Pay attention to yourself and to the teaching. Continue in them, for in doing this you shall save both yourself and those who hear you. 1Tim. 4:12-16
Let us offer our bodies as living sacrifices to Messiah, and bring our time and our habits to subjection to Him. As we trust in Him, He will provide the power and grace to bring our lives under His control. We will be productive and fruitful through Him. For He that abides in Him bears much fruit.