Ps. 69.5 (the king's confession)

O God / you know / my folly
my guilty deeds / are not hidden / from you. 

If we were correct in our previous reflections regarding the nature of the speaker as a king and his need to restore “what he did not steal” then these lines make a great deal of sense—the king’s ‘folly and guilty deeds’ would refer to his losing of the lands that had been given over to his protection. This resolves the seemingly random confession of guilt in a psalm that otherwise speaks of a profound sense of innocence in the face of suffering. Further, it also bleeds into the following verses where the king’s ‘folly and guilt’ have the very real danger of ‘putting to shame’ others who ‘wait for God’. If the king is guilty for the physical loss of items (land) given over to him for protection, then his loss of those items would be the source of great shame for his flock. It is their ‘glory’ (their land) that he has lost and, more importantly, opened them up, therefore, to threat and exploitation. Importantly, this verse sets up a theme that will be very prevalent throughout the remainder of the psalm: reproach, shame and humiliation. And, more importantly, it all turns on this verse regarding the king’s ‘folly and guilty deeds’. Everything begins to flow from this original confession.