I spent more time trying to figure out who the twelve disciples were and all their different alternate names than I did drawing any spiritual meaning out of this text. So let's talk about how we can get all these names straight. Matthew lists the twelve disciples as: Simon (Peter), Andrew, James, John, Philip, Bartholomew, Thomas, Matthew, James, Thaddaeus, Simon the Zealot and Judas Iscariot.
Now let's open it up for questions. Wasn't there supposed to be another Judas? Yes, the other Judas is mentioned in Luke and John. Judas or Jude is thought to be another name for Thaddaeus. Think of him as Judas/Thaddaeus. And what about Nathanael? Don't I recall a Nathanael in there somewhere? Yes, Nathanael is mentioned in John's Gospel and is thought to be another name for Bartholomew. Think of him as Bartholomew/Nathanael.
If you can get those two problem areas straight there should be no difficulty in memorizing the twelve disciples. (Unless of course you already have it memorized through a Sunday school song that you learned as a kid, but I didn't grow up in Sunday school so I have to come up with some other device.) My device is to memorize the names either as pairs or as repeats. The first eight names belong in four pairs and are easy to remember because every list in the Gospels presents them together.
Peter (Simon) and Andrew
James and John
Philip and Bartholomew (Nathanael)
Matthew and Thomas
Peter and Andrew and James and John are brothers of course, but I don't know why Philip and Bartholomew and Matthew and Thomas are always paired up. I just know that your ear just gets used to the rhythm of hearing their names spoken together.
The last four names are repeats, that is, they repeat another name in the list. You just need to remember which names show up twice:
James (son of Alphaeus)
Simon (the Zealot)
Judas (also Thaddaeus)
For me it's easier to remember that there are two Judases and that the good Judas has the alternate name of Thaddaeus, than to remember that there is a guy named Thaddaeus and then try to figure out where he fits into the whole scheme of things. Simon the Zealot, of course, is a repeat of Peter's other name, which isn't hard to remember since Jesus often addresses Peter as "Simon Peter."
So in sum there are four pairs of names and four repeats. Four and four. Now, can you list the twelve disciples without looking?