These are direct pointers. Wisdom is something immediate and directly accessible by all. Some of these might work better for you than others depending on the individual constitution of the mind. Nevertheless, the thing pointed to is the one underlying current without which no thought or experience could be possible.
These are “sayings of the secret-knowers.” As such, one might find contradiction on the level of terminology. One must recognise that words and meaning shift according to time and perspective: even if two contradictoary statements are found, the import of both is the same. Thus we can make use of paradox in the way of “everything is nothing; nothing is everything,” or “only the self exists; the self is entirely non-existent.”
The purpose of these paradoxes is not to cement some intellectual understanding in the mind; rather, their aim is the absolute destruction of such a thing called “mind,” which could only ever be an obscuring bundle of preconceived notions and beliefs. Wisdom is freedom from belief. Use these words to remove beliefs from yourself; not to add to them.