The Sefer Chovot Halevavot lists 7 factors that all contribute to developing trust in another.
Hashem is the only one who possesses all 7 and in an infinite measure.
1) Hashem loves and cares for each and every one of us infinitely.
2) He is watching over us 24/7 and actively taking care of all our needs.
3) No one, even ourselves, knows better than Hashem does what is truly good for us.
4) Hashem has infinite resources to help us whenever He so wishes in whatever way He wishes.
5) No one can harm or help us if Hashem doesn’t wish for it to happen.
6) He has been there for us since the moment we stepped into the world and He will always be by our side right until our final moment
7) There is no one more kind, compassionate and caring than Him