From the Fathers

"A man cannot acquire hope in God, unless he first fulfills His will as much as he is able. For hope in God and courage of heart are born of the testimony of conscience, and only through truthful testimony of our mind can we have trust in God. Testimony of the mind consists in the fact that conscience in no way accuses a man of negligence in anything he ought to do within his powers. `If our heart condemn us not, then have we confidence toward God' (1 Jn. 3:21). So confidence comes from progress in virtues and a good conscience."

St. Isaac of Syria