(Supposedly) Holy books and ethics?

Imagine I build a robot using the Biblical (or Qur'anic, or whatever) behavioral injunctions as algorithms, so that the robot acts in complete accord with these rules. Will this robot be ethical, or only mimic what some might call ethics? This leads to my actual question; can someone functioning from externally given rules (like those in a book) be called ethical, or are they simply mimicing moral-like behavior?