What did Thingol mean by his challenge?

“Go your way therefore! Bring to me in your hand a Silmaril from Morgoth’s crown; and then, if she will, Lúthien may set her hand in yours. Then you shall have my jewel; and though the fate of Arda lie within the Silmarils, yet you shall hold me generous.” - King Thingol, The Silmarillion (Of Beren and Luthien)

What did Thingol really mean when he told Beren he must first win a Silmaril before he could marry Luthien? Here are some possible interpretations (first two are from the book)

1.) Thingol does actually want a Silmaril, which seems to be how Beren interpreted the challenge. This is probably not the case, considering how Thingol shows little interest in the gems prior to this instance. Beren’s interpretation also suggests that Thingol values the Silmaril equally to his own daughter (as Beren points out). However, Thingol clearly loves his daughter above all else; the reason he doesn’t want her to marry Beren in the first place is because it would mean losing her.

2.) The quest was just creative way of getting Beren killed; this is the interpretation of most characters in the tale. Since Thingol promised Luthien he would not slay Beren, he would just send Beren on a quest that would surely get him killed. Therefore, he would keep his promise to Luthien and still get his way.

3.) Thingol just meant “Bring to me in your hand a Silmaril from Morgoth’s crown” as  something along the lines of “when pigs fly”. Its possible he never meant for Beren to go on the quest, assumed he would take the challenge as meaning “not in a million years”, and stay away from Luthien.

4.) Finally, my favorite interpretation: Thingol was teasing Beren. Thingol is one of the few characters from the First Age who purposefully says things in jest. For example, in The Unifinsihed Tales when Nellas begins her account of what happened to Turin with “Lord, I was sitting in a tree” and then she stops short, he smiles and responds with “Others have done that also, but have felt no need to tell me of it.” Ha ha! So, it’s totally possible that he was making a joke at Beren’s expense. In fact, in an earlier version of the tale from Beren and Luthien, Thingol was laughing and thought the challenge was hilarious until Beren made it clear that he was actually going to do it.

In my opinion, Thingol probably meant some combination of numbers 2, 3, and 4. He likely gave Beren the task as a teasing way of saying “no chance”. Then, when Beren took the quest literally, Thingol saw it as an opportunity to make sure he never marries Luthien. 

What do you think?