In philosophical sense the thought must rest, so that the anxiety in existential sense can stop

The thought is necessary on some levels, but when the thinking in philosophical sense projects itself as the past and the future, and produces anxiety as well as secureness, the mind is becoming absent, and the inevitable result hereof is unreality, emptiness, boredom and ennui.

So in philosophical sense the thought must rest, so that the anxiety in existential sense can stop.