How does the Bais Halevy define Bitachon?

When a individual strengthens his bitachon to the point that he is certain that everything that happens, will certainly be done for his good, thereby completely nullifying his own will to Hashem’s will, as it says in Tehillim קלא, ב: Surely I have behaved and quieted myself, like a child who is weaned from his mother; my soul is like a weaned child; he has reached bitachon.

See more: ‘A Life With Bitachon’