Gospel of Thomas, Logion 2 (Commentary)

(2) Jesus said, "Let him who seeks continue seeking until he finds. When he finds, he will become troubled. When he becomes troubled, he will be astonished, and he will rule over the All."

At the beginning of the path the Gnostic must take, he has not found Gnosis, so he must seek it before he can find it. When he finds it, he becomes troubled, because he is now exposed to the truth, and the truth isn't pretty: this isn't everything - there's more - we're trapped here in a lesser form, etc. This is effectively the awakening of the Gnostic to the prison of the Cosmos and the Demiurge. However, once he has become troubled, which is a necessary step, he will them realise that what at first seems like a terrible situation is actually a lot better than he first suspected. Yes, our Divine Spark is trapped, but before we awoke we did not know we had a Divine Spark, for our consciousness was dulled and tempered. Thus, the Gnostic then becomes astonished by the realisation that he can realise a great and monumental potential, the potential hidden within that Divine Spark. Then truly he rules over "the All" (the Fullness, the Pleroma) because, through his Divine Spark, he is the All, and thus is merely ruling over himself.