Our minds take the level of the things on which our thoughts dwell, and if we think upon earthly things, we shall fail to take the impress of that which is heavenly. We would be greatly benefited by contemplating the mercy, goodness, and love of God; but we sustain great loss by dwelling upon those things which are earthly and temporal. We allow sorrow and care and perplexity to attract our minds to earth, and we magnify a molehill into a mountain.... Temporal things are not to ... engross our minds until our thoughts are entirely of the earth and the earthly. We are to train, discipline, and educate the mind so that we may think in a heavenly channel, that we may dwell on things unseen and eternal, which will be discerned by spiritual vision. It is by seeing Him who is invisible that we may obtain strength of mind and vigor of spirit.... (OHC 339.3) MC VC