In his letter to Nun Eusebia, we are offered a unique and intimate glimpse into St Nektarios' role as a spiritual father. Here the saint uses his extensive knowledge and wisdom to encourage his spiritual daughter along the monastic path she has chosen to walk. Nevertheless, these lessons are equally beneficial to Christians living in the world, yet desire to grow in their love and devotion to God.

"The dangers which come from the desires of the heart, the considerations thereof, are as enormous as those from the thoughts of the mind because they are treacherous. The sources of different desires, considerations, and thoughts are the works of the hand and the works of the mind; the impulses of the nous and the impulses of the heart. As it were, the sources of the material and spiritual world are insufficient, and oftentimes they spring from external suggestions."