As our sages teach, "Think good, and it will be good"—positive thoughts lead to positive outcomes. Encourage him to trust in G-d, as explained in sacred texts, and to increase Torah study and mitzvah observance, as there is always room to grow in divine service. Chassidic teachings note that even Moses' soul continues to ascend in Gan Eden.
https://www.torahrecordings.com/rebbe/igroskodesh/014/005/5118