[smvoice]

Matt. 16:18 is well known and argued around here. Peter was named Petros in the Greek: a fragment of a rock.

Compare that to John 1:42: "Thou shalt be called Cephas, which is by interpretation, A STONE."

Back to Matt. 16:18. "And upon this rock (Petra)..." An immovable stone.

So if Peter's name means in Greek a fragment of a rock, and in Aramaic a stone, then we can get a pretty good idea how big this rock/stone was. Pretty sure it wasn't "immovable". But Christ, the Rock IS immovable.

[Al Hitan]

Bible Dictionary

Cephas definition
a Syriac surname given by Christ to Simon (John 1:42), meaning "rock." The Greeks translated it by Petros, and the Latins by Petrus.

Easton's 1897 Bible Dictionary

Strong’s Concordance

Képhas: "a rock," Cephas, a name given to the apostle Peter
Definition: Cephas (Aramaic for rock), the new name given to Simon Peter, the apostle.

NAS Exhaustive Concordance

Word Origin
of Aramaic origin

Definition
"a rock," Cephas, a name given to the apostle Peter

"Thou shalt be called Cephas, which is by interpretation, A STONE."

The Greek in that verse says petros, which is correct since the name he is given is Rock, and the for the gender to agree with Peter's maleness it is Petros.

[daniel1212]

In contrast to Peter, that the LORD Jesus is the Rock (“petra”) or "stone" (“lithos,” and which denotes a large rock in Mk. 16:4) upon which the church is built is one of the most abundantly confirmed doctrines in the Bible (petra: Rm. 9:33; 1Cor. 10:4; 1Pet. 2:8; cf. Lk. 6:48; 1Cor. 3:11; lithos: Mat. 21:42; Mk.12:10-11; Lk. 20:17-18; Act. 4:11; Rm. 9:33; Eph. 2:20; cf. Dt. 32:4, Is. 28:16) including by Peter himself. (1Pt. 2:4-8) Rome's current catechism attempts to have Peter himself as the rock as well, but also affirms: “On the rock of this faith confessed by St Peter, Christ build his Church,” (pt. 1, sec. 2, cp. 2, para. 424) which understanding many other of the ancients (whom Trent forbade disagreeing with, though she does) concur with.

While men can argue about the significance of the difference between the Greek (the language the Holy Spirit chose to express the New Testament revelation in) words “Petros” (Peter, or stone in Jn. 1:42) and “petra” (rock) in Mt. 16:18, and what the LORD might have said in Aramaic, it may be worth noting that the phrase “this stone” (“touton lithosis”), used to identify the cornerstone which is the foundation of the church, (Mt. 21:42) is only used of Christ as regarding a person. (Mt. 21:44)