Chapter IV. Of the lightness of the soul which may be compared to a wing or feather. For the nature of the soul is not inaptly compared to a very fine feather or very light wing, which, if it has not been damaged or affected by being spoilt by any moisture falling on it from without, is borne aloft almost naturally to the heights of heaven by the lightness of its nature, and the aid of the slightest breath: but if it is weighted by any moisture falling upon it and penetrating into it, it will not only not be carried away by its natural lightness into any aerial flights but will actually be borne down to the depths of earth by the weight of the moisture it has received. So also our soul, if it is not weighted with faults that touch it, and the cares of this world, or damaged by the moisture of injurious lusts, will be raised as it were by the natural blessing of its own purity and borne aloft to the heights by the light breath of spiritual meditation; and leaving things low and earthly will be transported to those that are heavenly and invisible. Wherefore we are well warned by the Lord’s command: “Take heed that your hearts be not weighed down by surfeiting and drunkenness and the cares of this world.” 1587 And therefore if we want our prayers to reach not only the sky, but what is beyond the sky, let us be careful to reduce our soul, purged from all earthly faults and purified from every stain, to its natural lightness, that so our prayer may rise to God unchecked by the weight of any sin. 1587     S. Luke xxi. 34 .