Q: Can you provide any insight as to why the gospel readings for the 2nd Sunday in ordinary time come from John in all three cycles of readings (A, B, C), rather than from the expected Synoptic?
A: Yes, I can.
In the previous missal, the Baptism of the Lord was observed on a weekday, and the gospel of the wedding at Cana was used on the Second Sunday after Epiphany, keeping in sequence the three great manifestations to the magi, to John at the Jordan, and to the guests at Cana.
The group revising the lectionary decided on a three-year cycle very early on, but they put the wedding at Cana on the Sunday after Epiphany all three years of the cycle, thinking that the Baptism would still take place on a weekday.
When the baptism moved to a Sunday, the gospel about the wedding at Cana dropped to the Second Sunday in Ordinary Time, still on all three years of the cycle. One of the early drafts permitted an alternative gospel (John 4:46-54)—the second miracle that Jesus performed at Cana—but that did not remain.
The chairs of the various study groups reviewed the final draft of the lectionary in April of 1968, and they requested a cycle of three different gospels for the Second Sunday in Ordinary Time across years A, B and C, instead of repeating the account of the wedding at Cana each year. They argued that the Second Sunday held no special significance, as, say, the Epiphany did, which has a gospel that does repeat all three years. They recommended adding John 1:29-34 in Year B, and John 1:35-42 presumably for Year C, keeping the wedding in Year A. This in part responded to objections from a couple of members of the lectionary’s own study group that John was underrepresented during Ordinary Time, having cited John 1:35-51 as one example of significant verses that were missing from Sunday proclamation.
Between that meeting and the publication of the lectionary in 1969, those readings were added to the Second Sunday, but on different years of the cycle than the chairs envisioned. It appears that the final distribution respects the biblical sequence of the three passages, spread over all three years, the latest of the three (the wedding) going into Year C.
This and more trivia will be part of a book I’ve submitted to Liturgical Press. If all goes well, you should have access to it within a year.