The present position study provides arguments about different aspects of Grecian Maxims (Grice 1975) within the Persian socio-cultural, Islamic setting. According to one of the most reliable Islamic Shiite sources, Man La Yahdhoroh Al-Faghih (Vol. 4), people are allowed to tell lie in some circumstances, for specific purposes, e.g. in battlefields, out of discretion, for building up reconciliation among people, and when promising to secure family relations and foundations. Also, based on the Holy Quran, telling lie to save life, properties and family from real enemies, which is regarded as Taqiyyeh; namely, guard-avoidance (Holy Quran, Surah Al-Imran, 28; An-Nahl, 106; Al-Mo’min, 28) is permissible. This qualitative study is, therefore, aimed at investigating ethics in the Holy Quran, as a highly culture-specific element, to explain and exemplify the above-mentioned cases and demonstrate that ethics is a missing maxim in the framework of Grecian Cooperative Principles, at least in two respects, 1) ethics should govern Grice’s Maxim of Quality and 2) Maxim of Ethics does not allow us to draw on unpleasant, offensive discourse.