What we know for sure is the God-inspired words of the New Testament written in Greek and not in Aramaic. The Bible itself interprets the meaning of Cephas with regards to the apostle in John 1:42: "And he brought him to Jesus. Now when Jesus looked at him, He said, “You are Simon the son of Jonah. You shall be called Cephas” - which is translated, A Stone (petros)." The real issue is not the exact meaning of "this rock" in Matthew 16.
“Sa paggalaw ng biyaya ng Banal na Espiritu at pagtawag ng Ama, kami ay naniniwala kay Jesus at inihahayag naming na: ‘Ikaw ang Cristo, ang anak ng buhay na Diyos.’ Sa ‘bato’ (pundasyon) ng ganitong pananampalatya na inihayag ni San Pedro, itinatag ni Cristo ang Kaniyang iglesiya.’ (saknong 424).