Ishmael and Isaac:

Ishmael was the first son of Abraham, the common patriarch of the Abrahamic religions, through his wife Sara's handmaiden Hagar. According to biblical tradition, he is the ancestor of the Arabs. Abraham's sons often reaped the consequences of their father's impatience. Zechariah and Elizabeth raised Mary - perhaps as Elizabeth's handmaid. Zechariah's first son was John according to the New Testament. But such may be a way for the writers to sever or hinder the connection between Zechariah and Abraham - or it may be karmic fulfillment in that Isaac was supposed to be the firstborn son. For if Zechariah had conceived through Elizabeth, Mary would not have been needed. In this manner, John - like Isaac - is legitimate, whereas Jesus - like Ishmael - is illegitimate. However, if the first-born is to be regarded as the inferior human embodiment and the second-born the spiritual manifest, this would explain how the first-born is assimilated with the Arabs: Isaac was the second-born (spiritual) Ishmael, just as Jesus was the second-born John, just as Dionysus was the second-born Zagreus, Osiris the second-born Seker, etc.

Since G=K in Egyptian, consonants were not doubled, and vowels were intermingled, Haggar could be equated to Heka:

Heka is the primeval potency that empowered the creator-god at the beginning of time.
In the Coffin Texts, Spell 261, it says that Heka existed "before duality had yet come into being"
Heka acted together with Hu, the principle of Divine Utterance, and Sia (divine omniscience) which all three were necessary for the King's creative powers during the Old Kingdom. Morenz calls this 'the expression of divine creativeness through thought and speech.' This was made visible in the image of the cobra on the King's brow, which could be named Weret-Hekau, 'the Goddess great in Heka-power'.

It is therefore worth noting that fourteen years had transpired between the births of Ishmael and Isaac, just as Mary (the born anew Elizabeth) was fourteen years old when Jesus was born. 

Abraham was initially meant to have just Isaac. But because he grew impatient with God, he couldn't wait any longer for a miracle. So he and his wife devised a plan to have a baby through other means. Upon arrival in the promised land, God assured Abraham that He would provide the region to his descendants (Genesis 12:7). “And the LORD said to Abram,… ‘Lift your eyes now and look from the place where you are—northward, southward, eastward, and westward; for all the land which you see I give to you and your descendants forever’ ” (Genesis 13:14-15). Was Zechariah muted because he likewise grew impatient with God? Obviously the above is wordplay: Abraham was banished from several lands, and his ancestors were to be subjects of other nations, not the nobility of such. Rulers in his day were considered living gods, and as such, by a ruler telling him to leave, it would be synonymous with being told "you are to go there". What this "god" was stating, was that he was going to disperse Abraham's offspring.

God continued: “And I will make your descendants as the dust of the earth; so that if a man could number the dust of the earth, then your descendants also could be numbered” (Genesis 13:16). Significantly, God later changed Abram’s name to Abraham (Genesis 17:5). His earlier name meant “high (exalted) father.” God renamed him “father of a multitude,” saying, “I will make you exceedingly fruitful; and I will make nations of you, and kings shall come from you” (Genesis 13:6). Again, god was going to scatter Abraham's descendants, not make them rulers of the earth. The changing of a name story was a ruse: to destroy one's name in Judaism, is the same as destroying that person. The name change was for one of three reasons: to either destroy Abram in disgrace, to point out a transition in Abraham's station (not unlike Pharaohs and Popes changing their names when the ascend to the thrones or the papacy) or as an alias in order to hide Abram's criminal behavior. The "definitions" of the terms Abram and Abraham are subjective: a word can be defined or expanded upon later to hide or alter its original meaning.

At the time these prophecies must have seemed ironic to Abraham, for his wife Sarah was barren. Her infertility was to be very significant in the development of the modern Middle East. God promised Abraham in Genesis 15:4 that he would have an heir: “one who will come from your own body.” Impatient, Sarah told Abraham to take her Egyptian handmaid Hagar and to produce a child by her. This took place “after Abram had dwelt ten years in the land of Canaan” (Genesis 16:1-3).” How did God tell this to Abraham? Perhaps through the archangel Gabriel? In the south of France- where Mary sailed to after the crucifixion, Mary was referred to as "Sarah the Egyptian, the sun-burnt one", which was not only a contradiction, but in a biblical context, a biting insult if Jesus was truly the Christ, as Hagar was the one recorded in the Old testament as being an Egyptian handmaid. Could one not see Elizabeth telling Zechariah to produce an heir through Mary, whom was raised by Zechariah as a maiden in their house?

“So he went into Hagar, and she conceived. And when she saw that she had conceived, her mistress became despised in her eyes” (Genesis 16:4). Fearing the wrath of Sarah, Hagar fled the land after conceiving the first son of Abraham. Is this why after having been raised in the house of Zechariah and Elizabeth, Mary was suddenly "sent away" some time shortly before conceiving (or perhaps after conceiving)? Mary was approximately 14 years old when she conceived - she must have been staying with Zechariah shortly before then. Why the sudden departure from Zechariah's house in her formative teen years? Chances are, she was still living there, and the Joseph figure was a fraud. She only left after it was revealed that she had conceived the son of Zechariah. 

However, a heavenly word was delivered to Hagar, instructing her to return. It comforted her that her son would have many children and descendants, although they will live in aversion with the other families and nations. Genesis 16:10-12 states: The angel added, “I will increase your descendants so much that they will be too numerous to count.” The angel of the LORD also said to her: “You are now pregnant and you will give birth to a son. You shall name him Ishmael, for the LORD has heard of your misery. He will be a wild donkey of a man; his hand will be against everyone and everyone’s hand against him, and he will live in hostility toward all his brothers.” This heavenly word was Gabriel telling her to return to Zechariah's house - that Elizabeth was herself pregnant, and as such forgave Mary since Elizabeth's child would be the legitimate Christ. 

Fourteen years after the birth of Ishmael, God graced Abraham with a second son, a step-brother to Ishmael conceived with his wife, Sarah. God instructed Abraham to name their son Isaac (meaning “laughter” for the skeptical response of Abraham when informed he and Sarah would have a son in their old age and the happiness he would bring to his parents, Genesis 17:17-19; Genesis 18:10-15; Genesis 21:5-6). Here, husband and wife conceive a child long after Abraham had conceived an illegitimate child with a concubine, whereas in the New testament, husband and wife conceive a child six months prior to the illegitimate conception of a child through a concubine. Notice that Abraham doubted the conception of a son, resulting in the child's name being modified, which is precisely what had happened regarding Zechariah and John (Elizabeth "named" John while Zechariah was unable to speak).

Note that the Old Testament states that there was an age difference between Ishmael and Isaac of 14 years: that was the same amount of time that Mary was on this earth before conceiving.