text: are priest not allow to memorize the mass i notice the priest reading from the bible every time he says mass? when the priest says mass he reads from the book, he should be able to say mass without reading from the book. no it is important for a priest to read from the order of the mass. every word was be said exactly as it is written. it ia a mortal sin to drop or add anything from the missal. it is dangerous to memorize the words because you can always forget.