The Prophet sallahu alayhi wa salam said:

Two eyes will never be touched by the fire of Hell; an eye which weeps out of Fear of Allah and an eye which spends the night in guarding in the Cause of Allah

[Saheeh Targheeb on. 1229]

Also, in the Hadith about the seven people Allah will shade on the Day of Judgment when there will be no shade but His shade, it mentions:

“…a man who remembers Allah in seclusion and his eyes are then flooded with tears…”

[al-Bukhari no. 6806]