What’s going on here is that you have absorbed a fairly common myth among lay Catholics, particularly among lay Catholics who do not attend daily Mass.
First, the cycle of readings for Sundays and Holy Days follows a three-year cycle. So, on Sundays and Holy Days you read from Year A, Year B, or Year C. On those days there is a first reading (typically from the Old Testament, but sometimes from the Acts of the Apostles), a Responsorial Psalm, a Second Reading (from the New Testament), and a Gospel Reading. This three-year cycle gives very good coverage of the Gospels, alright coverage of the New Testament, and poor coverage of the Old Testament.
We are currently in Year B. If you look at this table, for example, you should be able to see that the readings on a given Sunday are different this year (Year B) than they were last year (Year A), and different again from what they will be next year (Year C).
catholic-resources.org/Lectionary/1992Canada.htm
My Bible has a nicer table than that, which makes it clearer, but I couldn’t find similar online.
You can also look at this table, to get an idea of how much of each Bible book you hear by attending Sundays and Holy Days:
catholic-resources.org/Lectionary/Index-Sundays.htm
Overall, by attending Sundays and Holy Days, you hear 3.7% of the Old Testament (excluding the Psalms, which are used more heavily), and 40.8% of the New Testament. You’ll have heard 57.8% of the Gospels.
What about daily Mass? The readings at daily Mass follow a two-year cycle, independent of the three-year cycle for Sundays and Holy Days. We are currently in Year II. In the Season of Easter, the weekday Mass readings are the same in both years:
catholic-resources.org/Lectionary/1970USL-WeekdaysA.htm
In Ordinary Time, the First Reading and Responsorial Psalm are different in Year I and Year II, but the Gospel remains the same. There is no Second Reading in daily Mass:
catholic-resources.org/Lectionary/1970USL-WeekdaysB.htm
If you attend daily Mass, you will hear 13.5% of the Old Testament (excluding Psalms) and 71.5% of the New Testament, including 89.8% of the Gospels.
catholic-resources.org/Lectionary/Statistics.htm
The idea that you will hear the whole Bible is a myth, a strangely tenacious myth. Some Old Testament books are not used at all.
This table, unfortunately without percentages, shows when various parts of the Bible (including Psalms) are used in readings, psalms, antiphons, and acclamations in all sorts of Masses. It’s interesting to see what is and isn’t used:
adtelevavi.110mb.com/RomanRiteOF.htm (
WARNING: very large page)
Now we just need something similar, with percentages, that also includes the verses used as part of the Order of Mass.
If you also pray the Liturgy of the Hours (as priests and religious do), then you’ll have almost (but not quite) complete coverage of all the Psalms.
- Three psalms (58, 83, and 109) have been omitted from the psalter cycle because of their curses; in the same way, some verses have been omitted from certain psalms, as noted at the head of each. The reason for the omission is a certain psychological difficulty, even though the psalms of imprecation are in fact used as prayer in the New Testament, for example, Rv 6:10, and in no sense to encourage the use of curses
ewtn.com/library/CURIA/CDWGILH.HTM#Ch%20III-IV
You will have no extra coverage of the Gospels (the Gospels are excluded from the Liturgy of the Hours).
- The two-year cycle of readings for the liturgy of the hours is so arranged that each year there are readings from nearly all the books of sacred Scripture as well as longer and more difficult texts that are not suitable for inclusion in the Mass. The New Testament as a whole is read each year, partly in the Mass, partly in the liturgy of the hours; but for the Old Testament books a selection has been made of those parts that are of greater importance for the understanding of the history of salvation and for deepening devotion.
The complementarity between the readings in the liturgy of the hours and in the Mass in no way assigns the same texts to the same days or spreads the same books over the same seasons. This would leave the liturgy of the hours with the less important passages and upset the sequence of texts. Rather this complementarity necessarily demands that the same book be used in the Mass and in the liturgy of the hours in alternate years or that, if it is read in the same year, there be some interval in between.
(ibid)
Note that the Book of Ruth, for example, is absent from the readings at Mass, but included in the Liturgy of the Hours.
In summary: if you never read the Bible yourself, but faithfully attend Mass, you will hear the most important parts of the Bible, and will be presented with the history of salvation. If you attend daily Mass, and even follow the Liturgy of the Hours fully, you still will not hear the whole of the Bible, but you will hear the most important parts more often, and will be presented with a fuller version of the history of salvation.
If you want to read the whole Bible, get a Bible and read it! Some of my favourite bits are not included in the Mass readings, because they are ultimately not as important for understanding the plan of salvation.
Sorry for the long reply, but this is a common misconception and I hoped to provide the most helpful links I know of for future enquirers.