Many have expected that God would keep them from sickness merely because they have asked Him to do so. But God did not regard their prayers, because their faith was not made perfect by works. God will not work a miracle to keep those from sickness who have no care for themselves, but are continually violating the laws of health and make no efforts to prevent disease. When we do all we can on our part to have health, then may we expect that the blessed results will follow, and we can ask God in faith to bless our efforts for the preservation of health. He will then answer our prayer, if His name can be glorified thereby. But let all understand that they have a work to do. God will not work in a miraculous manner to preserve the health of persons who are taking a sure course to make themselves sick, by their careless inattention to the laws of health. MM 13.4
Those who will gratify their appetite, and then suffer because of their intemperance, and take drugs to relieve them, may be assured that God will not interpose to save health and life which are so recklessly periled. The cause has produced the effect. Many, as their last resort, follow the directions in the word of God, and request the prayers of the elders of the church for their restoration to health. God does not see fit to answer prayers offered in behalf of such, for He knows that if they should be restored to health, they would again sacrifice it upon the altar of unhealthy appetite.—Spiritual Gifts 4a:144, 145. MM 14.1