Is it of any significance for the country that the bible is the primary book for Peña Nieto and the other candidates for President of the Republic? Of course it is, and in my opinion in a negative sense.
I understand that for someone who aspires to be a minister, any theological text is certainly indispensable for their vocational education and training and morale. or any rabbi, deep knowledge of the Torah is essential, for the ayatollahs the full knowledge and even memorization of the Qur'an is essential and, in the same way, to Catholic bishops or ministers Christians, the bible must be the essential text for preaching.
Yet for the head of state of a secular, democratic republic of law, while the study of the Bible (or other dogmatic books) may be useful and even necessary, but not the primary and basic sustenance of one's knowledge and learning in order exercise one's political responsibilities.
For Peña Nieto, for López Obrador or whoever is the PAN candidate, it is more recommended and required to know Rousseau's Social Contract, Machiavelli's The Prince, and The Declaration of the Rights of Man, and if they want to know something of caciques and and caudillos, it is pertinent to read Pedro Páramo, The Tyrant Banderas, or the Shadow of the Tyrant.