As master and disciples stood together on the bank taking counsel, they saw, up at the head of the current, a man poling a little skiff down toward them.

A boat, on cue, from upstream. 棹 is zhào, to work a boat along with an oar - seven times in the chapter, and the man is identified by that verb before he is identified by anything else at all.

The Tang Monk said gladly, "Disciples, a boat is coming — call to him to ferry us across."

The master is delighted, which the reader should not be.

Sha Monk called out loud and sharp, "You there, poling the boat — come and ferry us! Come and ferry us!"

厲聲高叫, a loud sharp hail, and then the call twice over. Repeating a shout is how the storyteller marks a voice carrying across water.

The man in the boat said, "This is no ferry-boat — how should I ferry anyone?"

Here is the hook, and it is a good one: a man who says he does not ferry people, and then ferries people. If he had simply agreed, nobody would have wondered about him.

Sha Monk said, "In heaven and among men alike, kindness comes first."

方便 is the Buddhist upāya, skilful means - but by the Ming it had long since come down in the world into ordinary politeness, which is where Sha Monk is using it. It never left: it is the 方便 of a convenience store and of instant noodles, and 行個方便 is still how you ask a stranger to do you a small kindness. The 一 keeps its full yī at the end of the clause.

"Though yours is no ferry-boat, neither are we the sort forever coming to trouble you."

打攪, to be a bother - polite, everyday, and still exactly what you say when apologising for imposing. Sha Monk is answering an objection before it has finished being made.

"We are sons of Buddha, sent by the Court of the East to fetch the scriptures; do us the kindness of ferrying us across, and you shall have our thanks."

Now the credentials: an imperial commission and Buddhist standing, produced for a stranger on a riverbank. 差 in 欽差 is chāi, a commission from the throne, not the chà of falling short.

At these words the man poled his skiff in to the bank and, leaning on his oar, said, "Master, my boat is small and your party large — how can I ferry you all?"

He leans on his oar while he talks, which is the small physical detail that holds the boat still long enough for a conversation to happen in it.

Tripitaka went up and looked: the little boat, it turned out, was carved from a single log, with but one hollow amidships, room enough for two to sit.

One hollowed log, one seat, room for two. The boat's size is not scene-setting - it is the mechanism, because it forces the crossing into two trips and so splits the party.

Tripitaka said, "What is to be done?"

怎生是好, "what is to be done," is the spoken formula for an impasse. Tripitaka states the problem and leaves the solving to other people, as he almost always does.

Sha Monk said, "In that case, let us ferry over in two trips."

兩遭兒, in two trips, with 遭 counting a round journey. The 兒 is unstressed er.

Then Eight Rules, with a sly turn of mind, seeking to shirk and take the easy part, said, "Wujing, you and elder brother watch the baggage and the horse on this side; let me see the master over first and come back for the horse."

And here Pigsy is caught out by the narrator himself: 躲懶討乖, shirking and taking the easy part. His plan gets him a boat ride and leaves the others with the luggage. 看 is kān, to keep watch over, not the kàn of looking at.

"And let elder brother just leap across."

He assigns Pilgrim the jump and keeps the seat. 罷 is ba here, unstressed, softening an instruction - not the bà that means to stop.

Pilgrim nodded and said, "What you say is right."

Four words that cost them the master. Pilgrim, who has already noticed something wrong with the boatman, agrees to the arrangement anyway.