It may seen random or coincidental that the two meanings of the word reins: a bridle for a horse; or the kidneys, can be both be part of a physiological process which can guide and influence us.
O Lord, Search my Kidneys
Prepare Your Heart
Preparing our hearts doesn't involve special diets or exercise, it comes down to taking two simple steps: believing in Jesus Christ, and confessing our sins.
Heart Condition
Consider the cause and effect of heart condition. For example, which came first: smoking? or heart disease? What if heart disease is the result of a poor relationship with God, and that's the reason why we smoke?
Ecstasy
Peter's trance is designed to help him understand that the dietary restrictions of the Mosaic Law don't apply to Christians. By extension, this means that everyone can be a Christian, it is not just for the Jews.