Lucifer in heaven, before his rebellion, was a high and exalted angel, next in honor to God's dear Son. His countenance, like those of the other angels, was mild and expressive of happiness. His forehead was high and broad, showing a powerful intellect. His form was perfect; his bearing noble and majestic. A special light beamed in his countenance and shone around him brighter and more beautiful than around the other angels; yet Christ, God's dear Son, had the pre-eminence over all the angelic host. He was one with the Father before the angels were created.—The Story of Redemption, 13. TA 27.2
Lucifer was the covering cherub, the most exalted of the heavenly created beings; he stood nearest the throne of God, and was most closely connected and identified with the administration of God's government, most richly endowed with the glory of His majesty and power.—The Signs of the Times, April 28, 1890. TA 27.3
The Lord Himself gave to Satan his glory and wisdom, and made him the covering cherub, good, noble, and exceeding lovely.—The Signs of the Times, September 18, 1893. TA 28.1
Among the inhabitants of heaven, Satan, next to Christ, was at one time most honored of God, and highest in power and glory.—The Signs of the Times, July 23, 1902. TA 28.2
Lucifer, the “son of the morning,” in glory surpassing all the angels that surround the throne, ... [was] united in closest ties to the Son of God.—The Desire of Ages, 435. TA 28.3
Lucifer, “son of the morning,” was first of the covering cherubs, holy and undefiled. He stood in the presence of the great Creator, and the ceaseless beams of glory enshrouding the eternal God rested upon him.—Patriarchs and Prophets, 35. TA 28.4
He [Lucifer] had been the highest of all created beings, and had been foremost in revealing God's purposes to the universe.—The Desire of Ages, 758. TA 28.5