A well-balanced diet includes foods from all five food groups: fruits, vegetables, grains, protein, and dairy, while limiting unhealthy fats, sugar, and salt. Imagine someone saying that they are trying to eat healthy. They sit down with a well balanced meal. As soon as they are finished, they get up and go to the kitchen. They cut a very large piece of cake and wash it down with a coke. This is not a well balanced diet.
This happens in the spiritual sense as well. For example if you sit down to read your Bible and as soon as you are finished you gorge on some form of entertainment. Or if you pray for 5 minutes and watch hours of your favorite show, spend hours scrolling on social media, etc. This is not a well balanced spiritual diet. Your flesh does not like you filling yourself with healthy spiritual habits. It wants you to be filled with unhealthy spiritual habits that will weigh you down and keep you from exercising your faith.
Instead of unhealthy spiritual habits and get rid of all evil and all deceit and hypocrisy and envy and all slander. And yearn like newborn infants for pure, spiritual milk, so that by it you may grow up to salvation, if you have experienced the Lord’s kindness (1 Peter 2:1-3 NET).
Galatians 6:7-8 KJV 7 Be not deceived; God is not mocked: for whatsoever a man soweth, that shall he also reap. 8 For he that soweth to his flesh shall of the flesh reap corruption; but he that soweth to the Spirit shall of the Spirit reap life everlasting.