Musar su Salmi 101:6

The Holy One blessed be He desires only faithfulness (honesty). In regard to this scripture states: "G-d guards those who are faithful" (Tehilim 31:24), and "Open the gates and let the righteous people that keep faith enter in" (Isaiah 26:2), and "My eyes shall be on the faithful of the land so that they may dwell with Me" (Tehilim 101:6), and "are Your eyes not to faithfulness?" (Jeremiah 5:3).

Also, since one is prone to forgetfulness in these fine details, he will need diligent study in the books explaining these fine details to renew remembrance of them in his mind. Then certainly, he will be roused to fulfill them.

However, the factors which cause loss of this trait are all those detriments to the trait of Watchfulness, in addition to lack of proficiency in knowledge of the laws and ethics (Mussarim) as I wrote above. Our sages already stated: "an ignorant man cannot be pious" (Avot 2:5). For one who does not know cannot possibly do. Likewise they taught "great is study in that it brings one to doing" (Kidushin 40b).