Summary: Who should be baptised? Why should one be baptised? These are questions that must be answered by each one calling himself or herself after the Name of the Son of God.
“As they were going along the road, they came to some water, and the eunuch said, ‘Look, there is water! What is to stop me from being baptized?’” , 
Baptism is truly the water that divides. It is an unfortunate fact of ecclesiastical history that the rite has engendered such conflict among the followers of the Prince of Peace. When the Bible was being translated into the English language, the king commanded that words in common use were not to be translated. Thus, ecclesiastical words were adopted in the place of words more commonly used in the English tongue.
When King James commanded the Authorised Version, one of his stipulations was “that the old ecclesiastical words were to be kept.” ,  Because of this royal command we now commonly use the word “church” instead of “congregation.” Likewise, we use “baptise” rather than “immerse.” This was in reaction to the usage of such terms by the Puritans.  In fact, as one of the specific demands of the King, the translators had to accept the thirty-nine articles of the English church ; these dealt with rites and ceremonies. Thus, any aspect of the translation that appeared to point out the deviation in practise from what was written was to be rejected.
James was offended by the marginal notes of the Geneva Bible and the Bishop’s Bible, believing them in a couple of instances to be seditious; and he was offended by the growing influence of the Puritans who appeared to be influencing the populace toward a religion that depended less upon the clergy than upon the Bible itself. The practical consequence, in terms of our study this day, is that multiple lines of thought arose among the professed people of God concerning the initial rite of all who call themselves Christian.
Some worshippers are insistent that the act of baptism was necessary to secure salvation. Others imagine that baptism plays a part in salvation, though they are unwilling to make the act itself salvific. Still others imagine that it is the sign and seal of a follower of Christ—a necessary mark for disciples. Other professing Christians reject the need for baptism all together, insisting that the desire to follow Christ was sufficient to identify one as a Christian. In the face of such contradictory views, the only sure solution is to appeal to what is written in the Word of God.
The incident that serves as the backdrop for our text is worthy of review. Here is the account as provided in a newer translation. “An angel of the Lord spoke to Philip: ‘Get up and go south to the road that goes down from Jerusalem to Gaza.’ (This is the desert road.) So he got up and went. There was an Ethiopian man, a eunuch and high official of Candace, queen of the Ethiopians, who was in charge of her entire treasury. He had come to worship in Jerusalem and was sitting in his chariot on his way home, reading the prophet Isaiah aloud.
“The Spirit told Philip, ‘Go and join that chariot.’
“When Philip ran up to it, he heard him reading the prophet Isaiah, and said, ‘Do you understand what you’re reading?’
“‘How can I,’ he said, ‘unless someone guides me?’ So he invited Philip to come up and sit with him. Now the Scripture passage he was reading was this:
He was led like a sheep to the slaughter,
and as a lamb is silent before its shearer,
so He does not open His mouth.
In His humiliation justice was denied Him.
Who will describe His generation?
For His life is taken from the earth.
“The eunuch replied to Philip, ‘I ask you, who is the prophet saying this about—himself or another person?’ So Philip proceeded to tell him the good news about Jesus, beginning from that Scripture.
“As they were traveling down the road, they came to some water. The eunuch said, ‘Look, there’s water! What would keep me from being baptized?’ [And Philip said, ‘If you believe with all your heart you may.’ And he replied, ‘I believe that Jesus Christ is the Son of God.’] Then he ordered the chariot to stop, and both Philip and the eunuch went down into the water, and he baptized him. When they came up out of the water, the Spirit of the Lord carried Philip away, and the eunuch did not see him any longer. But he went on his way rejoicing” [ACTS 8:26-39 HCSB]. 
At this time, those who were saved were not called Christians. It was sometime after this that believers came to be known as Christians. Luke writes, in ACTS 11:26, “In Antioch the disciples were first called Christians.” Nevertheless, there can be no doubt that this Ethiopian official was converted to Jesus Christ. Moreover, his conversion preceded his baptism.