The Society of Biblical Literature Greek Text (minus accents):
’Αρχη του ’ευαγγελιου ’Ιησου χριστου.

Note: See below regarding the missing phrase “son of God.”

The Delitzsch Hebrew text (from the Delitzsch Hebrew Gospels, Vine of David):
תְּחִלַּת בְּשׂוֹרַת יֵשׁוּעַ הַמָּשִׁחַ בֶּן–הָאֱלֹהִים

Tekhillat besorat Yeshua HaMashiakh ben-haElohim.

The English Translation RSV:
The beginning of the gospel of Jesus Christ, the Son of God.

The English Translation DHE (Delitzsch Hebrew English, Vine of David):
The beginning of the good news of Yeshua the Mashiach, the son of God.

SHOULD “SON OF GOD” BE HERE?
Adela Yarbro Collins (Hermeneia Commentary) gives a compelling answer: the phrase “son of God” was almost certainly added by a scribe. It does exist in some good manuscripts (including Sinaiticus and Vaticanus). But it is virtually impossible to explain how a scribe would omit “son of God” on the introductory verse of the gospel, whereas it is easy to explain how a scribe would add “son of God” (since similar additions to add sanctity in depicting Yeshua happen in other places in the gospels).

If you are not used to the idea that manuscripts of the Bible vary in numerous details, a quick glance at the Wikipedia article, “Textual Variants in the New Testament,” should give you the idea.

WHAT DIFFERENCE DOES “SON OF GOD” MAKE?
Mark’s introductory verse is, arguably, a statement of his purpose throughout the gospel.

The way Mark tells the story of Yeshua, we see again and again the lofty but hidden identity of Yeshua. Every single pericope (scene) in Mark seems designed to explore who he is. And the titles “Messiah/Christ” and “Son of God” both fit well with Mark’s writing.

If we assume Mark 1:1 did not originally say “son of God,” this does not necessarily weaken the view that the introductory verse is a statement of purpose. For Mark, we can guess that the whole issue of Yeshua’s hidden but lofty identity is wrapped up in the word Christ or Messiah. His gospel is about Yeshua the Messiah (Jesus the Christ). And “son of God” is appropriate to the way he reveals Yeshua later.

DELITZSCH’S TRANSLATION OF “BEGINNING”
Delitzsch could have used reshit for beginning but opted for tekhillat instead. Some commentators think Mark was evoking the beginning of Genesis (bereshit, or “in the reshit“). Delitzsch chose instead tekhillat, a word used 21 times in the Hebrew Bible for the onset of a period of time.

This is rather more like Hosea 1:2 (“when the Lord began to speak through Hosea” or “when the Lord first spoke through Hosea”) than Genesis 1:1.

In other words. Delitzsch considered (presumably) and rejected the idea of an allusion to Genesis. He saw Mark 1:1, rather, as referring to the beginning of a new era, the era of the good news. Collins and some other commentators think “beginning” refers not just to the period covered in the book of Mark itself, but even beyond the end of Mark. The place where Mark picks up the story is the beginning of something new in the history of the world. It is tekhillat besorah, the beginning of the [era of] good news in Messiah.

BESORAH-GOSPEL-GOOD NEWS
In the Hebrew Bible, the word for tidings from a messenger can be neutral (good or bad tidings) or in some cases it seems to imply good tidings (even without the adjective good being used). This is an example of a confusing and vague connotation for a word in another language. If you were to ask, “Does besorah mean simply news or good news?” the answer would have to be, “It depends on context.”

Besorah is used 6 times in the Hebrew Bible and its verb form, mevasser, is used also 6 times.

There is something significant in that the earliest language describing the impact of Yeshua on the world (Mark and Paul as examples) uses besorah (“good news” or “tidings from a messenger”) and not simply davar (“word” or “message”). A word from a messenger is inherently important, about something crucial and perhaps even a matter of life or death. The story of Yeshua is not just any word or message. It is world changing, as in the inscription about Caesar Augustus at Priene in Asia Minor: “the birthday of the god was for the world the beginning of joyful tidings which have been proclaimed on his account” (cf. Daniel Harrington, Sacra Pagina commentary).

A form of the Greek euangelion translates the Hebrew mevasser of Isaiah 52:7 in the Septuagint (LXX). Isaiah 52:7 in the RSV reads, “How beautiful upon the mountains are the feet of him who brings good tidings.”

“Gospel” is a word deriving from Middle English (God-spell) and seems to be based on the idea that hearing the story of Jesus can put you under the God-spell (change your life with divine power). It is one of those religious words we probably ought to use less often. It is one of many examples of perfectly normal words that have become confusing due to religious use (favor-grace, rescue-salvation, gospel-tidings).

CHRISTOU: NAME OR TITLE?
Delitzsch’s Hebrew translation puts the definite article into Yeshua HaMashiakh whereas the Greek text has not definite article (Iesou Christou). In other words, Delitzsch seeks to clarify Christ-Messiah as a title and downplay the possibility it came to be used like a name.

Mark can distinguish between the two kinds of usage. Compare Mark 1:1 with Mark 8:29:
1:1, Iesou Christou, Yeshua Messiah.
8:29, su ei ho Christos, you are the Messiah.

Collins thinks that “Christ” came to be used as a name in the early movement, though its roots clearly came from the title, “the Christ” or “the Messiah.”

EVALUATING DELITZSCH
Delitzsch has made some decisions with which I disagree. He opts to keep “son of God” in the verse in spite of the more likely explanation that it was added later. He opts to make “Messiah” and title and not reproduce it as a name, though evidence is to the contrary.

Still, all translation involves reproducing the original idea from one culture into a different one. In making a Jewish edition of the gospels in Hebrew, it is reasonable that Delitzsch would use “Messiah” in the more familiar Jewish manner.

Delitzsch has also made decisions with which I agree: using tekhillat for beginning instead of trying to evoke Genesis and using besorah for gospel/good-news.

SUMMARY
Mark 1:1 is statement of purpose, a statement about the identity of Yeshua, and a statement about the impact of Yeshua on the world. Mark’s purpose will be to show Yeshua the Nazarene as Yeshua Messiah (or Yeshua the Messiah). He will define “Messiah” by the things he shows Yeshua doing and saying.

Mark also makes a statement about Yeshua’s identity: he is worthy of the name Messiah.

And he makes a statement in this verse about the impact of Yeshua on the world: he is good tidings from heaven, a world changing figure whose life story begins a new era.