Hi, Matthew. No wonder you don't understand all the riddles. That's because not all of the exchanges are riddles. And some of them don't actually make any sense.

Verse one just tells what's going on. The boy is going to school carrying books and bundles (of food, probably.)

2nd verse should say "I came a-walking by your door,"

"That lay in your way,"

Means that the door of the boy's home safely kept the devil out.

Verse 3: "Flung your dog a stone,"
"I wish it was a bone,"

I suppose you could say the boy is chiding the devil for being mean and throwing a stone rather than a bone. Hey, it rhymes.

Verse 4: "Oh, what sheep and cattle's that,"
"They're mine and me father's,"
"The ones that have a blue tail,"

Since none of them have blue tails, the devil loses out.

Verse 5.
Part 1 is not a riddle. He simply defies the devil.
"Oh, then I get a share o' them,"
"You cannot get a share of them," says the wee boy and still he stood


Part 2; "And why the stick all in your hand,"
"To keep me from all cold and harm,"

Not a riddle. It isn't good politics for the boy to tell the devil that he holds the stick to hit the devil with, so he fudges the truth here.


Verse 6:
"Oh, I wish you were in yonder tree,"
"A ladder under me,"
A clever response. (The devil hopes he will fall out of a tall tree.)

Part 2:
"The ladder it'll break,"
"And you will surely fall,"

This part is not so good. It ought to convey either that the ladder will fall on top of the devil or that the devil was climbing up the ladder when it broke under him.

Verse7:

"I wish you were in yonder sea," says the false knight on the road
"A good boat under me," says the wee boy and still he stood
"The boat will surely sink," says the false knight on the road
"And you will surely drown," says the wee boy and still he stood

Pretty good responses here, but the it would be better if we knew the devil was in the boat too.

Verse 8:

"Has your mother more than you," says the false knight on the road
"Oh, none of them for you," says the wee boy and still he stood

The devil is asking if his mother has more children than the boy. His reply is defiant but not a riddle.

Part 2
"I think I hear a bell," says the false knight on the road
"It's ringing you to hell," says the wee boy and still he stood

The bell is the school bell, of course. But the boy's reply, with its reference to hell, defeats the devil. This ties in with the superstition that if we know the real name of a supernatural foe, we defeat it. And that's the end of the song.

In the olden days, people did not want to actually say the devil's name. Good thing bell rhymes with hell!
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FYI, if you ever do encounter the devil on a lonely country road, the best way to defeat him is to say that Jesus and Mary will protect you. That produces instant results, or so I have read.