Was the great commission only commanded to the apostles?
"And Jesus came up and spoke to them, saying, 'All authority has been given to Me in heaven and on earth. Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, teaching them to observe all that I commanded you; and lo, I am with you always, even to the end of the age'" (Matthew 28:18-20).
Many people find Jesus' words awkward in this passage. It clearly shows Jesus commanding that people were to be baptized by other people; thus, eliminating baptism by the Holy Spirit as being the one baptism in Ephesians 4:4-6. It shows that people become disciples through baptism, which shoots a hole in the teachings of "faith alone" or "grace alone." The authority for baptism is in the name of the Father, Son, and the Holy Spirit, which destroys the argument that baptism can be only done in Jesus' name. It means three beings giving authority, which is awkward for those who claim that God is only one being. The result is that many seek to reclassify this passage as not applying, such as by claiming that it isn't original to the text or that it was only given to a limited audience.
Jesus was speaking to the eleven apostles (Matthew 28:16). It was his commission to them for what they must do in the future.
Not only were they to make disciples from all nations, but they were to teach these new disciples to observe all the commands that Jesus gave the apostles. Now think about it. The command that Jesus is currently giving the apostles would be included in all the commands that Jesus gave them. Thus, the command to baptize to make disciples would also be a command to later disciples. So would the command to pass on the teachings, just as Paul told Timothy, "The things which you have heard from me in the presence of many witnesses, entrust these to faithful men who will be able to teach others also" (II Timothy 2:2).
Jesus also promised to be with the disciples to the end of the age. The Christian age still continues but the apostles have left this world long ago. This wasn't a command meant to be limited to a short period of time or only for a few people.
The apostles were the start but they were by no means the exclusive recipients of this command.