The first stanza flows seamlessly into the second, as the words "Move forward" actually continue the thought begun in line 8. The speaker steps farther into the church and "run[s] [his] hand around the font" as he goes (10). The "font" he's referring to here is the stone basin that priests use to baptize people. He runs his hand over it, almost in a kind of caress.
From where I stand, the roof looks almost new— Cleaned, or restored? Someone would know: I don't.
Glancing up, the speaker notes that the roof of the church looks almost new. He's not sure if the thing has been cleaned or restored. These lines again demonstrate that the speaker (at least at this moment) is more interested in the everyday details about the church's construction than its spiritual significance.
He figures that someone would know if the roof's been cleaned or restored, but he doesn't. This kind of statement has a meaning beyond just wondering about the roof. It's the exact same attitude that this speaker takes toward religion in general. In the same way, he realizes that someone knows why the inside of this church is so important, but he doesn't.
Mounting the lectern, I peruse a few Hectoring large-scale verses, and pronounce 'Here endeth' much more loudly than I'd meant.
Lines 13-15 show the speaker really making himself at home in the empty church. He walks right up to the lectern and starts reading some of the passages from mass that are laid out on it. The verses are written in really large letters, which might suggest that many of the people giving the readings at mass are growing older.
The speaker decides to read the words "Here endeth" alone, and ends up speaking them much more loudly than he meant to. By that token, this idea of ending rings loudly in the church. Again, this isn't a coincidence! Our man Larkin is loudly putting forth the thought of ending—both in the church and in the reader's mind.
The echoes sn***** briefly. Back at the door I sign the book, donate an Irish sixpence. Reflect the place was not worth stopping for.
The "sn*****ing," or laughing, echoes of line 16 might suggest the senselessness of the Bible verse that the speaker has just read out loud. Or they might be laughing at the notion of ending in the church, which the speaker has just mentioned out loud. We think that both of these readings are available here. How about you?
After this, the speaker decides to go back to the door he came in through, and donates an "Irish sixpence" into the collection box. Readers of Larkin's time would've known that an Irish sixpence was, as a piece of currency, worthless in England. So, this is a very careless and jerky thing to do. After all, would you go into a church and donate an expired coupon for Shake n' Bake? (Mmm, Shake n' Bake…)
In any case, Larkin closes the stanza by having his speaker reflect that "the place was not worth stopping for" (18). At this point in the poem, the speaker has definitely taken a pretty hard shot at religion, and has proclaimed that it's all pretty much worthless after visiting the church.