Are there Two LORDS in Genesis 19:24?
וַיהוה הִמְטִיר עַל־סְדֹם וְעַל־עֲמֹרָה גָּפְרִית וָאֵשׁ
מֵאֵת יהוה מִן־הַשָּׁמָיִם׃
Then the LORD rained upon Sodom and upon Gomorrah brimstone and fire
from the LORD out of heaven...
Trinitarians and Binitarians have long used this verse as evidence for Jesus’ preexistence. The argument was made as early as about 150 ce by Justin Martyr (Dialogue cum Tryphone Judaeo 56):
…and He is the Lord who received commission from the Lord who [remains] in the heavens, i.e., the Maker of all things, to inflict upon Sodom and Gomorrah the [judgments] which the Scripture describes in these terms: ‘The Lord rained down upon Sodom and Gomorrah sulphur and fire from the Lord out of heaven.’
And just recently the Catholic scholar Eugen J. Pentiuc defends this interpretation (Pentiuc 2005:68): 
In Genesis 19:24, the one Yahweh, whom Abraham greeted as ’ădōnāy, “Lord,” makes the fire and brimstone rain down on Sodom and Gomorrah, “from (mē’ēt) Yahweh, out of heaven.” Therefore, the basic idea in Genesis 19:24 is that YHWH on earth is in agreement and cooperating with YHWH in heaven, in whatever he is doing.
Probably the best argument against the preexistence interpretation is to marshal other examples where a subject noun is repeated in the same sentence. The following are a sampling of such verses.
וַיִּקַּח אַבְרָהָם אֶת־יִשְׁמָעֵאל בְּנוֹ
וְאֵת כָּל־יְלִידֵי בֵיתוֹ
וְאֵת כָּל־מִקְנַת כַּסְפּוֹ
כָּל־זָכָר בְּאַנְשֵׁי בֵּית אַבְרָהָם
‘and Abraham took Ishmael his son,
and all that were born in his house,
and all that were bought with his money,
every male among the men of the house of Abraham’
וַיְהִי בְּרֶדֶת מֹשֶׁה מֵהַר סִינַי
וּשְׁנֵי לֻחֹת הָעֵדֻת בְּיַד־מֹשֶׁה
‘and it was in the coming down of Moses from mount Sinai
and two tables of testimony in the hand of Moses’
וְלָקַח הַכֹּהֵן מִלֹּג הַשָּׁמֶן וְיָצַק עַל־כַּף הַכֹּהֵן הַשְּׂמָאלִית׃
‘and the priest shall take of the log of oil and pour on the left palm of the priest’
וּמִן־הַשֶּׁמֶן יִצֹק הַכֹּהֵן עַל־כַּף הַכֹּהֵן הַשְּׂמָאלִית׃
‘and of the oil the priest shall pour on the left palm of the priest’
אָז יַקְהֵל שְׁלֹמֹה אֶת־זִקְנֵי יִשְׂרָאֵל
נְשִׂיאֵי הָאָבוֹת לִבְנֵי יִשְׂרָאֵל
‘then Solomon assembled the elders of Israel,
all the heads of the tribes,
the chief of the fathers of the children of Israel,
unto king Solomon’
וַתְּבִאֵנִי כַשְׂדִּימָה אֶל־הַגּוֹלָה בַּמַּרְאֶה
‘and a spirit lifted me up
and brought me to Chaldea to the captivity in vision
by the spirit of God’
Cordaro, John V. 2006. One Yahweh. Paper available on line at http://www.intergate.com/~jcordaro/One_Yahweh.html.
Coxe, A. Cleveland, translator. 1994. Ante-Nicene Fathers, Volume 1. The Apostolic Fathers, Justin Martyr, Irenaeus. Peabody, Massachusetts: Hendrickson Publishers, Inc. Originally published in the United States by the Christian Literature Publishing Company, 1885.
Pentiuc, Eugen J. 2005. Jesus the Messiah in the Hebrew Bible. New York: Paulist Press.
Rudd, Steve. Trinity Proof Texts: Gen 19:24. Undated on line article at http://www.bible.ca/trinity/trinity-texts-genesis19-24.htm.
 Translation is from Coxe (1994). Greek text:.... καὶ Κύριός ἐστι, παρὰ Κυρίου τοῦ ἐν τῷ οὐρανῷ, τουτέστι τοῦ τοιητοῦ τῶν ὅλων, λαβὼν τὸ ταῦτα ἀπενεγκεῖν Σοδόμοις καὶ Γομόῤῥοις, ἅπερ ὁ λόγος καταριθμεῖ, οὕτως εἰπών, “Κύριος ἔβρεξεν ἐπὶ Σόδομα καὶ Γόμοῤῥα θεῖον καὶ πῦρ παρὰ Κυρίου ἐκ τοῦ οὐρανοῦ.”
 See also the website of Steve Rudd.
 See also Cordaro (2006).