It is not enough that one surrenders oneself. Surrender is to give oneself up to the original cause of one's being. Do not delude yourself by imagining such a source to be some God outside you. One's source is within oneself. Give yourself up to it. That means that you should seek the source and merge in it.
If one wants to abide in the thought-free state, a struggle is inevitable. One must fight one's way through before regaining one's original primal state. If one succeeds in the fight and reaches the goal, the enemy, namely the thoughts, will all subside in the Self and disappear entirely.