Who was the Ethiopian Eunuch?
Church Father St. Irenaeus of Lyons in his book Adversus haereses (Against the Heresies, an early anti-Gnostic theological work) 3:12:8 (180 AD), wrote regarding the Ethiopian eunuch, “This man (Simeon Bachos the Eunuch) was also sent into the regions of Ethiopia, to preach what he had himself believed, that there was one God preached by the prophets, but that the Son of this (God) had already made (His) appearance in human flesh, and had been led as a sheep to the slaughter; and all the other statements which the prophets made regarding Him.” In Ethiopian Orthodox Tewahedo tradition he was referred to as Bachos and in Eastern Orthodox tradition he is known as an Ethiopian Jew with the name Simeon also called the Black, a name used in Acts 13:1– Wikipedia
He was already in Jerusalem worshiping. Why? A religious tradition of worshiping the one true God dated back to the time of King Solomon. Solomon was so famous that people traveled from all over to see him and hear his wisdom. One of the ones who came was the Queen of Sheba.
The Queen of Sheba(1 Kings 10:1-13)
This is important because it appears that she was impregnated by Solomon and her son from him became the King of Ethiopia.
Ethiopia’s history as recorded and elaborated in a 13th-century treatise, the Kebre Negest, asserts descent from a retinue of Israelites who returned with Makeda, the Queen of Sheba from her visit to King Solomon in Jerusalem, by whom she had conceived the Solomonic dynasty’s founder Menelik I. As Solomon was of the tribe of Judah, his son Menelik I would continue the line, which according to Ethiopian history was passed directly down from king to king until Emperor Haile Selassie I (ostensibly the 225th king from King David) was deposed in 1974.– Wikipedia
The eunuch was worshiping in Jerusalem in accordance with prophecy:
From beyond the rivers of Ethiopia my suppliants, even the daughter of my dispersed, shall bring mine offering.(Zephaniah 3:10) KJV
The connection between Judah and the Lion goes back to Jacob’s prophecy on his death bed.
Judah, thou art he whom thy brethren shall praise: thy hand shall be in the neck of thine enemies; thy father’s children shall bow down before thee. Judah is a lion’s whelp: from the prey, my son, thou art gone up: he stooped down, he couched as a lion, and as an old lion; who shall rouse him up? The sceptre shall not depart from Judah, nor a lawgiver from between his feet, until Shiloh come; and unto him shall the gathering of the people be.(Genesis 49:8-10) KJV
The Lion of the Tribe of Judah is the Lord
And I saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals. And I saw a strong angel proclaiming with a loud voice, Who is worthy to open the book, and to loose the seals thereof? And no man in heaven, nor in earth, neither under the earth, was able to open the book, neither to look thereon. And I wept much, because no man was found worthy to open and to read the book, neither to look thereon. And one of the elders saith unto me, Weep not: behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof.(Revelation 5:1-5) KJV
So the Ethiopian Eunuch already believed in the Lion of the Tribe of Judah, and now Phillip is able to show him that Jesus Christ is the very same. Under the guidance of the Holy Spirit, no doubt Phillip was able to connect the dots between Jesus, the lineage of David, and the Lion of the Tribe of Judah.