We were reading the story in the Grimnismal where Thor went on a trip with Loki. Loki behaved himself for once. They stopped at a peasant's home where Thor slaughtered the goats that draw his chariot and allowed them to be cooked for dinner, since the peasant did not have enough to feed his guests. The only proviso was that the bones were to be left intact but the peasant's son, Thjalfi, broke one of the bones for the marrow. So, in the morning, when Thor hallowed the bones with his hammer and brought the goats back to life, one of them was lame. Thor was angry but the peasant was so frightened that he took pity. Rather than kill the entire household, he took Thjalfi and his sister as servants with him.
Then, when they were looking for a place to sleep that night, they found an empty hall and slept in a small side chamber. The next morning, they realized that they had been sleeping in a giant's glove and a rather large one at that. Thor's normal reaction upon seeing a giant is to take up his hammer, Mjollnr, and give him/her a smack with it. When Skrymir stood up; Thor was too astonished to give him a whack. Snorri makes fun of Thor and makes him look like a meat-head. He said Thor failed to hit him and then what follows is some comical attempts by Thor to open the food bag, which he cannot untie, followed by Thor losing his temper and giving the sleeping Skrymir a thwack over the head. Skrymir wakes up and asks him if a leaf has fallen on his head. Thor waited for him to fall asleep again and struck him again, with the hammer going deep into his skull. This time Skrymir woke and asked if an acorn had fallen on his head. Thor tried one more time just before dawn and still Skrymir woke up and asked if some birds had dumped some litter on him.
Is Snorri making fun of Thor? Maybe. Snorri was a Christian. I think Skrymir's size makes it understandable that Thor was taken aback at first. At least Thor was capable of thinking and not just mindlessly going in to attack mode. I think his difficulties make him endearing. When Thor and his companions went to sleep in the glove, Thor stood at the entrance to keep watch. The Old Norse said that Thor took thought to protect himself. The pronoun 'sik' is in the accusative form, object of the infinitive, and is the most damning part of the story. However, Thor did stand in the doorway and keep watch all night. Anyone who wanted to get at Thjalfi, Roskva and Loki would have to get past him first. Clearly he was not just taking thought for his own protection alone. Later in the tale, Thor's strength and determination impress and frighten even Skrymir.