If I renounce speaking about God perhaps it is because I have been taught or found out for myself that the concepts of my language are inadequate to God. If I renounce sweets it is perhaps because I recognize the limitations of my metabolism, or perhaps the limitations of my discipline.
But what of the renunciation of the picture of mental processes? Is this renunciation in obedience to a limitation?
"But surely you can't deny that, for example, in remembering, an inner process takes place." -- What gives the impression that we want to deny anything? When one says, "Still, an inner process does take place here" -- one wants to go on: "After all, you see it." And it is this inner process that one means by the word "remembering". -- The impression that we wanted to deny something arises from our setting our face against the picture of an 'inner process'. What we deny is that the picture of an inner process gives us the correct idea of the use of the word "remember". Indeed, we're saying that this picture, with its ramifications, stands in the way of our seeing the use of the word as it is.(PI, Sec. 305)
Or in another place:
As I have often said, philosophy does not call on me for any sacrifice, because I am not denying myself the saying of anything but simply giving up a certain combination of words as senseless. In a different sense, however, philosophy does demand a renunciation, but a renunciation of feeling, not of understanding. Perhaps that is what makes it so hard for many people. It can be as hard to refrain from using an expression as it is to hold back tears, or hold in anger.
Is this renunciation in obedience to a limitation? If it were a denial of mental processes, it would be easy to understand it in this way. However, Wittgenstein is explicit that "[t]he great difficulty here is not to present the matter as if there were something one couldn't do. As if there really were an object, from which I extract a description, which I am not in a position to show anyone." Wittgenstein here denies denial as an explanation of his thinking. There is in this special denial a development of the position taken in the Tractatus. Here Wittgenstein's thinking becomes more musical. In the Tractatus, Wittgenstein thought that he could draw a picture of the other side of a limitation and deny this picture, provided that this denial came under erasure--under the retractions applying the general renunciation of propositions: the ladder thrown away.