An obvious detail is that Jesus chose the apostles in the presence of witnesses. Perhaps he did this to ensure that no one afterwards could say about them that Jesus had not chosen them. If that was the case, then we can see the care that Jesus took in ensuring that they would be known as his special servants.
It may be the case that Luke mentions the order in which they were chosen on this occasion. Or maybe he is mentioning them in the order with which they had come to follow him. We are not told how the last five came to be his followers, but we are told elsewhere about how the first seven came to follow him as their Master.
He gave to them a special name, that of apostles. We are so used to that title that we may not give much thought to what it signified. The word literally means messenger, which implies a sender and a recipient. An apostle is someone who delivers another’s message to those the sender wanted to hear it. This means that an apostle did not make up his own message, but had to be faithful to the One who sent him.
Who were to be the recipients of the message of Jesus? We can answer this question by saying that basically there would be two groups of recipients. One we call the unconverted and the other we can call the converted. So the apostles would always have both types of listener in mind as they went delivering the message of Jesus.