600
Χ χ     chi, χι     [kʰ]     [x] ~ [ç]

60
Ξ ξ     xi, ξι     [ks]
Σ σ/ς[note 1]     sigma, σίγμα     [s]     [s] ~ [z]
Ε ε[note 2] epsilon, έψιλον     [e]

6
Σ σ/ς[note 1]     sigma, σίγμα     [s]     [s] ~ [z]

Notes

1)The letter sigma Σ has two different lowercase forms, σ and ς,
with ς being used in word-final position and σ elsewhere.

2)Epsilon ε and omicron ο originally could denote both short and long vowels in pre-classical archaic Greek spelling, just like other vowel letters. They were restricted to the function of short vowel signs in classical Greek, as the long vowels /eː/ and /oː/ came to be spelled instead with the digraphs ει and ου, having phonologically merged with a corresponding pair of former diphthongs /ei/ and /ou/ respectively.

Phoenician     Greek
Phoenician samekh     /s/     Greek Xi     Ξ     xi         /ks/
Phoenician šin         /ʃ/     Greek Sigma Σ     sigma     /s/

In the cases of the three historical sibilant letters below, the correspondence between Phoenician and Ancient Greek is less clear, with apparent mismatches both in letter names and sound values. The early history of these letters (and the fourth sibilant letter, obsolete san) has been a matter of some debate. Here too, the changes in the pronunciation of the letter names between Ancient and Modern Greek are regular.
Letter     Name     Pronunciation
Greek         Phoenician original     English     Greek (Ancient)     Greek (Modern)     English
Ζ     ζῆτα     zayin                     zeta         [zdɛːta]             [ˈzita]         /ˈziːtə/, US /ˈzeɪtə/
Ξ     ξεῖ, ξῖ samekh                     xi             [kseː]                 [ksi]             /ˈzaɪ/, /ˈksaɪ/
Σ     σίγμα     šin                     siɡma         [siɡma]             [ˈsiɣma]         /ˈsɪɡmə/

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Use as numerals

Greek letters were also used to write numbers. In the classical Ionian system, the first nine letters of the alphabet stood for the numbers from 1 to 9, the next nine letters stood for the multiples of 10, from 10 to 90, and the next nine letters stood for the multiples of 100, from 100 to 900. For this purpose, in addition to the 24 letters which by that time made up the standard alphabet, three otherwise obsolete letters were retained or revived: digamma ⟨Ϝ⟩ for 6, koppa ⟨Ϙ⟩ for 90, and a rare Ionian letter for [ss], today called sampi ⟨Ͳ⟩, for 900. This system has remained in use in Greek up to the present day, although today it is only employed for limited purposes such as enumerating chapters in a book, similar to the way Roman numerals are used in English. The three extra symbols are today written as ⟨ϛ⟩, ⟨ϟ⟩ and ⟨ϡ⟩ respectively. To mark a letter as a numeral sign, a small stroke called keraia is added to the right of it.


Ε ε     epsilon     5
could be mistaken for
Ξ ξ     xi     60
or
Σ σ     sigma     200

A contract for goods or services could vary on slight penmanship as to rather you pay 200 or 60 or 5.

Ζ ζ     zeta     7
or
Σ σ     sigma     200
are also similiar

All depends on rather the writer is perfect & the paper doesnt get damaged.

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We shall start this research with 

p47-revelation-13.jpg

Σ     sigma    200
Σ • (uppercase S, lowercase σ)

600 200 6

Greek Letters	google translate	notes
Χ Σ ς	L S q
ΧΣς	ChSs
Σ ς	S. As
Σς	pp
Σ Σ Σ	S S S
ΣΣΣ	SAA
ΧΣΣ	CHSS
σ	p p
σσ	SS
Χσσ	Chss

The shape and alphabetic position of sigma is derived from Phoenician shin ש ش שׂ ש س In Judaism Shin also stands for the word Shaddai, a name for God.


The name of sigma, according to one hypothesis,[1] may continue that of Phoenician Samekh.

According to a different theory,[2] its original name may have been san (the name today associated with another, obsolete letter), while sigma was a Greek innovation that simply meant "hissing", based on a nominalization of a verb σίζω (sízō, from earlier *sig-jō, meaning 'I hiss').
Stigma (ϛ) is a ligature of the Greek letters sigma (Σ) and tau (Τ), which was used in writing Greek between the Middle Ages and the 19th century. It is also used as a numeral symbol for the number 6. In this unrelated function, it is a continuation of the old letter digamma (originally Ϝ, cursive form Greek Digamma cursive 01.svg), which had served as a numeral since antiquity and was conflated with the σ-τ ligature in the minuscule handwriting of the Middle Ages.


Uppercase forms of stigma as a numeral (Ϛ) are rare in practice; when they occur, they can often be confused with uppercase forms of another numeral symbol, koppa (Ϟϟ), which stands for 90.

*************************************
Ε epsilon    5
Χ Ε ς
X R q

Χες
Hess

600 5 6
*************************************
Ξ xi    60
Χ Ξ ς
X O q

ΧΞς
ChXs

600 60 6
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Xi (uppercase Ξ, lowercase ξ; Greek: ξι) is the 14th letter of the Greek alphabet. It is pronounced [ksi] in Modern Greek, and generally /ˈzaɪ/ or /ˈsaɪ/ in English.[1] In the system of Greek numerals, it has a value of 60. Xi was derived from the Phoenician letter samekh Phoenician samekh.svg.

Xi is not to be confused with the letter chi, which gave its form to the Latin letter X.

ΞΞΞ
XXX

Ξ Ξ Ξ
O O O

Both in classical Ancient Greek and in Modern Greek, the letter Ξ represents the sound [ks]. In some archaic local variants of the Greek alphabet, this letter was missing. Instead, especially in the dialects of most of the Greek mainland and Euboea, the sound [ks] was represented by Χ (which in classical Greek is chi, used for /kʰ/). Because this variant of the Greek alphabet was used in Italy, the Latin alphabet borrowed Χ rather than Ξ as the Latin letter X.

Cyrillic
While having no Latin derivative, the Xi was adopted into the early Cyrillic alphabet, as the letter ksi (Ѯ, ѯ).







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christogram
https://en.wikipedia.org/wiki/Christogram
ICXC

In Eastern Christianity, the most widely used Christogram is a four-letter abbreviation, ΙϹ ΧϹ — a traditional abbreviation of the Greek words for "Jesus Christ" (i.e., the first and last letters of each of the words "ΙΗϹΟΥϹ ΧΡΙϹΤΟϹ, with the lunate sigma "Ϲ" common in medieval Greek),[18] and written with titlo (diacritic) denoting scribal abbreviation (І҃С Х҃С).

On icons, this Christogram may be split: "ΙϹ" on the left of the image and "ΧϹ" on the right. It is sometimes rendered as "ΙϹ ΧϹ ΝΙΚΑ", meaning "Jesus Christ Conquers." "ΙϹΧϹ" may also be seen inscribed on the Ichthys. In the traditional icon of Christ Pantokrator, Christ's right hand is shown in a pose where his fingers bend and cross to form the letters ΙϹ, Χ, and Ϲ.

https://en.wikipedia.org/wiki/File:ICXC_NIKA.svg
https://en.wikipedia.org/wiki/File:Spahr_63_1140_133312.jpg
https://en.wikipedia.org/wiki/File:The_Greek_Pantokrator_on_the_Hungarian_Holy_Crown.jpg
https://en.wikipedia.org/wiki/File:Christ_Pantocrator,_Church_of_the_Holy_Sepulchre.png
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https://en.wikipedia.org/wiki/Christian_symbolism


The use of nomina sacra has continued in iconography.
In this mosaic in Hagia Sophia, ΙΣ ΧΣ indicates Ἰησοῦς Χριστός, Jesus Christ.
https://en.wikipedia.org/wiki/Nomina_sacra#/media/File:Jesus-Christ-from-Hagia-Sophia.jpg


Christian symbolism is the use of symbols, including archetypes, acts, artwork or events, by Christianity.
The symbolism of the early Church was characterized by being understood by initiates only!
The shape of the cross, as represented by the letter T, came to be used as a "seal" or symbol of Early Christianity by the 2nd century. 200ad

Among the symbols employed by the early Christians, that of the fish seems to have ranked first in importance. Its popularity among Christians was due principally to the famous acrostic consisting of the initial letters of five Greek words forming the word for fish (Ichthus), which words briefly but clearly described the character of Christ and the claim to worship of believers: "Ἰησοῦς Χριστὸς Θεοῦ Υἱὸς Σωτήρ", (Iēsous Christos Theou Huios Sōtēr), meaning, Jesus Christ, Son of God, Saviour


https://en.wikipedia.org/wiki/Nomina_sacra
List of Greek nomina sacra
English Meaning     Greek Word     Nominative (Subject)     Genitive (Possessive)
God                 Θεός         ΘΣ                         ΘΥ
Lord                 Κύριος         ΚΣ                         ΚΥ
Jesus                 Ἰησοῦς         ΙΣ                         ΙΥ
Christ/Messiah         Χριστός     ΧΣ                         ΧΥ

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{\mathfrak {P}}4 (Suppl. Gr. 1120)     150–225    ΘΣ ΘΥ ΚΥ ΚΣ ΠΝΙ ΠΝΟΣ ΠΝΑ ΧΣ ΙΥ ΙΣ
https://en.wikipedia.org/wiki/Papyrus_4

https://en.wikipedia.org/wiki/Papyrus_4#/media/File:Papyrus_4_(Luk_6.4-16).jpg
Luke 6:4-16
Sign     P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}4
Text     Luke 1-6 (extensive parts of,)
Date     Late 2nd/3rd century
Script     Greek
Found     Coptos, Egypt
Now at     Paris, Bibliothèque Nationale, Suppl. Gr. 1120
Type     Alexandrian text-type
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https://en.wikipedia.org/wiki/Papyrus_46
{\mathfrak {P}}46 contains most of the Pauline epistles, though with some folios missing. It contains (in order) "the last eight chapters of Romans; all of Hebrews; virtually all of 1–2 Corinthians; all of Ephesians, Galatians, Philippians, Colossians; and two chapters of 1 Thessanians. All of the leaves have lost some lines at the bottom through deterioration."[3]


P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}46 (P. Chester Beatty II + P. Mich. Inv. 6238)  175–225
ΚΕ ΚΝ ΚΥ ΚΩ ΚΣ ΧΡΩ ΧΡΥ ΧΡΝ ΧΝ ΧΣ ΧΩ ΧΥ ΧΡΣ ΙΗΥ ΙΗΝ ΙΗΣ ΘΩ ΘΥ ΘΝ ΘΣ
ΠΝΑ ΠΝΙ ΠΝΣ ΥΙΥ ΥΙΝ ΥΙΣ ΥΝ ΣΤΡΕΣ ΣΤΡΝ ΣΤΡΩ ΣΤΡΟΣ ΣΤΡΟΥ ΕΣΤΡΟΝ ΕΣΤΡΑΙ
ΕΣΤΑΝ ΣΤΟΥ ΑΙΜΑ ΑΝΟΥ ΑΝΟΝ ΑΝΟΣ ΑΝΩΝ ΑΝΟΙΣ ΠΡΙ ΠΗΡ ΠΡΑ ΠΡΣ ΙΥ

A folio from P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}46 containing 2 Corinthians 11:33–12:9. As with other folios of the manuscript, text is lacunose at the bottom.
Name     P. Chester Beatty II; Ann Arbor, Univ. of Michigan, Inv. 6238
Sign     P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}46
Text     Pauline epistles
Date     c. 175–225
Script     Greek
Now at     Dublin, University of Michigan
Cite     Sanders, A Third Century Papyrus Codex of the Epistles of Paul
Size     28 cm by 16 cm
Type     Alexandrian text-type



https://en.wikipedia.org/wiki/Papyrus_46#/media/File:P46.jpg
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https://en.wikipedia.org/wiki/Papyrus_49

P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}49 (P. Yale 415 + 531)     200–300    ΚΩ ΘΥ ΘΣ ΙΥ ΠΝ ΧΣ ΧΥ ΧΩ

recto with text of Eph 4:16-29
Name     Papyrus Yale 415
Text     Epistle to the Ephesians 4-5 †
Date     3rd century
Script     Greek
Found     Egypt
Now at     Yale University Library
Cite     W. H. P. Hatch and C. B. Welles, A Hitherto Unpublished Fragment of the Epistle to the Ephesians, HTR LI (1958), pp. 33-37.
Size     18 x 25
Type     Alexandrian text-type

https://en.wikipedia.org/wiki/Papyrus_49#/media/File:Papyrus49verso.jpg

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https://en.wikipedia.org/wiki/Papyrus_66

{\mathfrak {P}}66 (P. Bodmer II +Inv. Nr. 4274/4298     150–200
ΚΣ ΚΥ ΚΕ ΘΣ ΘΝ ΘΥ ΘΩ ΙΣ ΙΝ ΙΥ ΧΣ ΧΝ ΧY ΥΣ ΥΝ ΥΩ ΠΝΑ ΠΝΙ ΠΝΣ
ΠΗΡ ΠΡΑ ΠΡΣ ΠΡΙ ΠΕΡ ΠΡΕΣ ΑΝΟΣ ΑΝΟΝ ΑΝΟΥ ΑΝΩΝ ΑΝΩ ΑΝΟΙΣ ΑΝΟΥΣ
ΣΡΩ ΣΡΟΝ ΣΡΟΥ ΣΡΘΗ ΣΡΑΤΕ ΣΡΩΣΩ ΕΣΡΑΝ ΕΣΡΘΗ

https://en.wikipedia.org/wiki/Papyrus_66#/media/File:Papyrus66.jpg

The manuscript contains John 1:1-6:11, 6:35b-14:26, 29-30; 15:2-26; 16:2-4, 6-7; 16:10-20:20, 22-23; 20:25-21:9, 12, 17. It is one of the oldest well-preserved New Testament manuscripts known to exist.

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https://en.wikipedia.org/wiki/Papyrus_75

Name     P. Bodmer XIV-XV
Sign     P {\displaystyle {\mathfrak {P}}} {\mathfrak {P}}75
Text     Luke 3:18-24:53 + John 1-15 (extensive portions of,)
Date     175-225 (Martin and Kasser), late third century-early fourth century (Orsini), fourth century (Nongbri)
Script     Greek
Found     Pabau, Egypt
Now at     Vatican Library, Rome
Cite     V. Martin, R. Kasser, Papyrus Bodmer XIV-XV
Size     26 cm x 13 cm
Type     Alexandrian text-type

https://en.wikipedia.org/wiki/Papyrus_75#/media/File:Papyrus_75a.gif

{\mathfrak {P}}75 (P. Bodmer XIV and XV)     
175–225
    ΙΣ ΙΗΣ ΙΥ ΙΗΥ ΙΝ ΙΗΝ ΘΣ ΘΝ ΘΥ ΘΩ ΚΣ ΚΝ ΚΥ ΚΩ ΚΕ ΧΣ ΧΝ ΧΥ

ΠΝΑ ΠΝΣ ΠΝΙ ΠΝΟΣ ΠΝΤΑ ΠΝΑΣΙ ΠΝΑΤΩΝ ΠΡΣ ΠΗΡ ΠΡΑ ΠΡΙ ΠΡΟΣ ΠΡ

ΥΣ ΥΝ ΥΥ ΙΗΛ ΙΛΗΜ ΣΡΟΝ ΣΤΡΟΝ ΣΡΩΘΗΝΑΙ

ΑΝΟΣ ΑΝΟΝ ΑΝΟΥ ΑΝΟΙ ΑΝΩΝ ΑΝΩ ΑΝΟΥΣ ΑΝΟΙΣ ΑΝΕ


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