A proverb meaning that a single firm resolve or strong faith can accomplish great things—faith or determination can move heaven.
受験の前に『一念天に通ず』と自分に言い聞かせ、最後まで努力した。
Before the exam I told myself 'ichinen ten ni tsūzu' and kept working hard until the end.
諦めずに続けることで道が開く場合がある。一念天に通ずということだ。
There are times when continual effort without giving up opens the way. That's what 'faith moves mountains' means.