Thanks for the welcome Tom.
I personally wouldn't call anything in the Holy Bible a riddle,
The reason I look for riddles is because God says he speaks in riddles, and even ties his glory to hiding things. Consider these passages, the word for "dark sayings" is the word for riddle:
Nu 12:8 With him will I speak mouth to mouth, even apparently, and not in dark speeches <02420>; and the similitude of the LORD shall he behold: wherefore then were ye not afraid to speak against my servant Moses?
Ps 49:4 I will incline mine ear to a parable: I will open my dark saying <02420> upon the harp.
Ps 78:2 I will open my mouth in a parable: I will utter dark sayings <02420> of old:
Pr 1:6 To understand a proverb, and the interpretation; the words of the wise, and their dark sayings <02420>.
Da 8:23 And in the latter time of their kingdom, when the transgressors are come to the full, a king of fierce countenance, and understanding dark sentences <02420>, shall stand up.
Pr 25:2 It is the glory of God to conceal a thing: but the honour of kings is to search out a matter.
Riddle is a literary form as much as metaphor and poetry. But Proverbs 1 says that the wise seek to understand the riddle,
When Jesus showed Peter where the scriptures said he must die, and when he showed the disciples on the road to Emmaus where all the scriptures spoke of him, and when he taught in the temple at age 12, he was showing them things which were not discernible using literal, grammatical, historical methods. otherwise they would not have been hidden.
Where is the cross reference for Jesus being called a Nazarene? Where is the cross reference where the scriptures teach that marriage does not endure to the resurrection? These are not found in the literal, but are easy to see in the prophetic riddle.