At this time God didn’t communicate with people anymore especially through visions (it’s quite rare). At night, while asleep, Samuel hears someone calling him. So he goes to Eli, thinking that it is he who calls him. It happens three times but Samuel hasn’t been in touch with God till now. Eli realizes it is God who speaks to Samuel. He tells Samuel to answer God and listen to him. And God tells Samuel to tell Eli that he is going to destroy his family because he didn’t do anything against his sons. And Samuel keeps growing with God’s favor.