I recently had this question from, and an interesting conversation with, a friendly inquirer into lectionary design, a Princeton Seminary graduate who has been through the RCL some 10 times, and who now works in Protestant campus ministry in NY.
"If people only hear/read the Bible during Sunday worship, and attend churches where the RCL is used, how much of the Bible will they never hear? And how much of the gospels will they never hear?"
At least that is the simplified version of the question that the Rev. Dr. Laurie Tiberi sent my way. In its original form, her question drew a fairly stark contrast between the Daily Lectionary and the "Sunday only" RCL. Here is my response, some of which will be familiar to those who have read Year D.
Thanks for the question.
Before I respond, I should say that when "Sunday only" is distinguished from the Daily Lectionary, there are some dozen events or so that are independent of the DL, but tend to fall on weekdays (fixed feasts, fasts, and other weekday events), like Christmas Day, Epiphany, Ash Wed, MTW of Holy Week, Maundy Thursday, Good Friday, Holy Saturday (Vigil), Ascension, Thanksgiving.
My hunch is the question was put to set the DL apart from RCL, which consists of some 70-72 events total. Some 60 of these are what we might call "Sunday only," combinations of texts that would fall on a Sunday, but obviously not every year. While there are only 52 weeks a year, [the Ordinary Time after] Epiphany, e.g., rarely gets all the Sundays assigned to it, since that only happens when Easter comes really late.
With all that said, I will admit the "Sunday only" question in the purest sense [RCL minus the fixed/weekday feasts] has been of concern to me, since many Protestant churches (I see you are laboring specifically in Protestant ministry) have not always done much historically with weekday services, even with Good Friday and Maundy Thursday. So I have often wondered, what will "Sunday only" attendees hear, and what will they miss, if they only hear the Bible in Church and never crack their own copies at home?
I have not crunched the numbers myself very precisely on the Bible as a whole (66 books of the Reformed/Protestant canon), but I believe David Ackerman's estimate of 24.9% coverage by the RCL is about right (see his book, Beyond the Lectionary). That figure, as I understand it, would include Sundays, plus those dozen or so high holy days. So, slightly less than a quarter of the Bible is covered by RCL.
Another figure that might be of interest: Dennis Olsen, Prof of OT at Princeton Seminary, has calculated that less that 20% of the OT is represented in the RCL.
As for the Psalms, my Presbyterian BOCW prints just the "semi-continuous" track through the RCL (as opposed to the complementary track that uses typological associations, allusions, and quotations to pair OT and NT readings). That semi-c track leaves 50 psalms completely untouched, to say nothing of omissions of verses from others psalms that it only reads partially (e.g., 78, 119, etc.) The RCL (semi-c + complimentary tracks, taken together) leaves more like 40 Psalms untouched. So between 26% and 33% of the Psalms are completely untouched by RCL. Again, the factor is higher if you count omitted verses from psalms that are used.
But you asked about the Gospels. When you asked specifically about Sunday only, I calculated that literally (and did not include the dozen feast/fast days), and came up with this: vv. used on Sundays / total vv. in Gospel = % used on Sundays ...
Matthew: 631 / 1071 = 58.92%
Mark: 461 / 678 = 67.99%
Luke: 690 / 1151 = 59.95%
John: 490 / 879 = 55.75%
Total: 2272 / 3779 = 60.12%
Now, two considerations need to be taken into account, one that would suggest significantly higher coverage and another significantly lower:
Higher: Bear in mind that the synoptic gospels often duplicate, even "triplicate" some material. I think the designers of RCL assumed that if we hear a parable in Matt 13, we do not necessarily need to cover it again in Mark 4, and any significant differences can be dealt with in a sermon. So, e.g., it may be Year A, but I think bringing in Mark's and Luke's take on the same text is fair game, esp. if their versions are not in RCL. That may not be of much help if we are interested in the overall structure of the particular gospel in question, but I think it is safe to say that the sayings of Jesus get better than 60% coverage. One exception that seems important to me is his saying about the narrow gate. Neither Matthew's nor Luke's version is ever touched. John's version of "I am the gate for the sheep" is used in RCL, but there is no mention of narrowness or the life or death ultimatum, so that seems to me a very different text. [UPDATED: Hence the two sermons on these texts in Chapter 4 of Groans of the Spirit.] The synoptic issue is also the reason I have tried to give John better coverage in Year D, since his material tends to be quite unique and does not have the benefit of synoptic redundancy.
Lower: If we really do stick with "Sunday only" (thus, setting aside the long Good Friday readings of the Passion Narratives), and if we assume (as is the case in most churches) that we opt for Palm Sunday, not the Passion Sunday read-through of the PNs, then nearly two whole chapters of the Gospels (Matt 26–27; Mark 14–15; Luke 22–23; John 18–19) are not in fact covered on Sundays at all (except for a few selected verses here and there). Those tend to be very long chapters. My calculations are a bit roughshod here, but that would drop the coverage factor by as much as 10%. So, arguably, the Gospels are only about half-covered (50%) when one drops out all the passion material that is unlikely to be read. Moreover, if it is read all in one clip (Passion Sunday), that leaves little time for preaching. This latter consideration I find particularly ironic in light of Martin Kahler's oft-cited description of the Gospels as "Passion Narratives with extended introductions." Such a definition, though hyperbolic perhaps, suggests the Gospel lections in RCL, in a sense, consist almost entirely of introductory material.
Again, thanks for the question. I hope you find this helpful.
Peace in Christ,