And Samuel was afraid to tell Eli the vision

1 Samuel 3:15
So Samuel lay down until morning,[b] and opened the doors of the house of the Lord. And Samuel was afraid to tell Eli the vision. 16 Then Eli called Samuel and said, “Samuel, my son!”
He answered, “Here I am.”

In this passage, the Lord told Samuel about His displeasure of Eli's household and that He will do something against that household. Samuel knew that it was the Lord who spoke but was initially reluctant to pass the message on, probably because he did not want to hurt Eli.

Part of the job of a prophet is to bring warnings against those who are walking opposite to God. Before Jesus' time, only selected people are chosen to be prophets. After Jesus' time, there is still the role of prophet, pastors, teachers, evangelists and so on. However, most of us who have the Holy Spirit in us, are meant to hear from God. And there will be occasions that God may want to use us to bring a word of warning to our brothers and sisters. Are we preparing ourselves to be used by God and deliver God's message or do we filter and censor God's messages?