"Before receiving this message from God, “Samuel did not yet know the Lord, neither was the word of the Lord yet revealed unto him;” that is, he was not acquainted with such direct manifestations of God's presence as were granted to the prophets. It was the Lord's purpose to reveal Himself in an unexpected manner, that Eli might hear of it through the surprise and inquiry of the youth. PP 582.1"
"Now Samuel did not yet know the Lord, neither was the word of the Lord yet revealed unto him."
EGW directly quotes and explains 1 Samuel 3:7.
"Samuel was filled with fear and amazement at the thought of having so terrible a message committed to him. In the morning he went about his duties as usual, but with a heavy burden upon his young heart. The Lord had not commanded him to reveal the fearful denunciation, hence he remained silent, avoiding, as far as possible, the presence of Eli. He trembled, lest some question should compel him to declare the divine judgments against one whom he loved and reverenced. Eli was confident that the message foretold some great calamity to him and his house. He called Samuel, and charged him to relate faithfully what the Lord had revealed. The youth obeyed, and the aged man bowed in humble submission to the appalling sentence. “It is the Lord,” he said: “let Him do what seemeth Him good.” PP 582.2"
"And Samuel lay until the morning, and opened the doors of the house of the Lord. And Samuel feared to shew Eli the vision."
EGW elaborates on the events described in 1 Samuel 3:15, expanding on Samuel's fear and Eli's reaction. It's more than a thematic parallel; it's a direct retelling and interpretation.
Yet Eli did not manifest the fruits of true repentance. He confessed his guilt, but failed to renounce the sin. Year after year the Lord delayed His threatened judgments. Much might have been done in those years to redeem the failures of the past, but the aged priest took no effective measures to correct the evils that were polluting the sanctuary of the Lord and leading thousands in Israel to ruin. The forbearance of God caused Hophni and Phinehas to harden their hearts and to become still bolder in transgression. The messages of warning and reproof to his house were made known by Eli to the whole nation. By this means he hoped to counteract, in some measure, the evil influence of his past neglect. But the warnings were disregarded by the people, as they had been by the priests. The people of surrounding nations also, who were not ignorant of the iniquities openly practiced in Israel, became still bolder in their idolatry and crime. They felt no sense of guilt for their sins, as they …
"He, that being often reproved hardeneth his neck, shall suddenly be destroyed, and that without remedy."
The EGW passage illustrates the principle of Proverbs 29:1 by showing how Eli's sons, Hophni and Phinehas, hardened their hearts despite repeated warnings, leading to their eventual destruction. It's a direct application of the proverb's teaching.