Really, anytime someone (especially a wizard) gives another person their True Name, which is a huge sign of trust, as knowing a thing's true name gives the user power over it.
A Wizard of Earthsea
Ged imagines his mentors in the art of magic all assembled looking at him, sad for his failure. And his Aunt, the village witch, who taught him his first spells is right there alongside Ogion and the Mages of Roke.
Vetch gives Ged his true name to call upon if he ever needs aid, and he does this after Ged massively screws up by conjuring the Gebbeth and causing the death of the Archmage.
The Tombs of Atuan
Ged giving Tenar back her name.
Ged: Take care, Tenar.
Later, Ged telling Tenar how much having contact with her meant to him.
Ged: One man alone has no hope, here. I was dying of thirst when you gave me water, yet it was not the water alone that saved me. It was the strength of the hands that gave it.
Ged and Tenar's Power of Trust conversation, as they discuss escaping from the labyrinth.
Tenar: They would not let us get out. Ever. Ged: Perhaps not. Yet it's worth trying. You have knowledge, and I have skill, and between us we have… Tenar: We have the Ring of Erreth-Akbe. Ged: Yes, that. But I thought also of another thing between us. Call it trust… That is one of its names. It is a very great thing. Though each of us alone is weak, having that we are strong, stronger than the Powers of the Dark. Listen, Tenar! I came here a thief, an enemy, armed against you; and you showed me mercy, and trusted me. And I have trusted you from the first time I saw your face, for one moment in the cave beneath the Tombs, beautiful in the darkness. You have proved your trust in me. I have made no return. I will give you what I have to give. My true name is Ged. And this is yours to keep. Let the ring be rejoined. Tenar: I will come with you.
Tehanu
Tenar comforting Therru whenever her Dark and Troubled Past and her disfigurement distress her.
Ged recovering from his depression due to having lost his powers by living with Tenar and falling in love with her.
