My fellow prisoner Aristarchus sends you his greetings, as does Mark, the cousin of Barnabas. (You have received instructions about him; if he comes to you, welcome him.)
NIV
Aristarchus my fellow prisoner wishes to be remembered to you, as does Mark the relative of Barnabas. You received instructions concerning him; if he comes to you give him a [hearty] welcome.
AMP
Aristarchus my fellowprisoner saluteth you, and Marcus, sister's son to Barnabas, (touching whom ye received commandments: if he come unto you, receive him;)
KJV