Laertes takes it, and folds it in both of his own. He's conscious of what it means to Galahad to offer his hand--it makes it hard for him to speak, and speaking is already so fraught between them.

Perhaps this gesture means that it's become less fraught. Perhaps it means that Galahad trusts their understanding now.

Laertes smiles, and lets him go again. "My thanks. Thou art a good friend to me."