Ketachon literally means "the one who withholds".
In 2 Thessalonians 2, that word refers to the will of God that determines when and how the end times will unfold.
In the microcosm (in us), it relates to how our inner Being tries to "hold back" or slow our karma and defects so we have a chance of working on ourselves.
"Do not worry; cultivate the habit of being happy." - Samael Aun Weor