Amulek warns us not to procrastinate the day of our repentance, because if we do not improve our time while in this life, "then cometh the night of darkness wherein there can be no labor performed." (Alma 34:33.) The "night of darkness" referred to by Amulek is that period of a person's existence when he loses the will to repent. Thus when a person loses the desire to repent or decides he is not going to repent, then his "night of darkness" has come whether it is in this life or in the life to come.