Be Attentive:

'Be attentive to yourself,' says Moses (Deut. 15:9.LXX) - that is, to the whole of yourself, not to a few things that pertain to you, neglecting the rest. By what means? With the intellect assuredly, for nothing else can pay attention to the whole of yourself. Set this guard, therefore, over your soul and body, for thereby you will readily free yourself from the evil passions of body and soul. Take yourself in hand, then, be attentive to yourself, scrutinize yourself; or, rather, guard, watch over and test yourself, for in this manner you will subdue your rebellious unregenerate self to the Spirit and there will never again be 'some secret iniquity in your heart' (Deut. 15:9).

St. Gregory Palamas , Those Who Practice a Life of Stillness no. 9, The Philokalia Vol. 4
edited by Palmer, Sherrard and Ware; Faber and Faber pg. 338-339