A Spark by Innocent Mwatsikesimbe from The Vision, chapter 49

A promise to yourself usually starts as a reaction. “Most of the promises we make to, or oaths we take on, ourselves are inspired by some negative circumstance” we would rather not live through again. New Year’s resolutions are the familiar case, and making them at all is the mark of a life trying to move forward.

The trouble is that the reaction fades. While the trigger is still around, the promise nearly keeps itself; once things change and the reason seems to have vanished, holding to it turns hard. That is the point where keeping your word actually means something.

Innocent’s answer is memory rather than willpower. Go back for the reason you made the promise in the first place, and from that reason “garner the strength to pull through the tempting phase.”