The term for I am pleased is closely related in the Peshitta - ܐܨܛܒܝܬ from the root צבי to will, desire. But the variations in the line all go back to the underlying idea I think that Jesus is the 'desired one' - a title associated by Muslims with the Hebrew root of Muhammad. I even think the very idea of 'sect' deriving its origin from the Greek 'to chose' might go back to this same Aramaic root as 'to will' often has the sense of 'to choose.' There is something here, I just can't put my finger on what.And behold, a voice from heaven, which said, This is my beloved Son, with whom I am pleased
Another example of the messianic implications of the terminology
Clearly the same passage was used by Sabbatai Tsevi (for obvious reasons) to bolster his messianic claims. But did this have some connection with the (Tz)ebionites? I think so.א"ר אלעזר מתים שבחוץ לארץ אינם חיים שנאמר (יחזקאל כו, כ) ונתתי צבי בארץ חיים ארץ שצביוני בה מתיה חיים שאין צביוני בה אין מתיה חיים
Rabbi Elazar said: The dead of the lands outside of Eretz Yisrael will not come alive and be resurrected in the future, as it is stated: “And I will set glory [tzvi] in the land of the living” (Ezekiel 26:20). This teaches that with regard to a land which contains My desire [tzivyoni], its dead will come alive; however, with regard to a land which does not contain My desire, i.e., outside of Eretz Yisrael, its dead will not come alive.
מתיב ר' אבא בר ממל (ישעיהו כו, יט) יחיו מתיך נבלתי יקומון מאי לאו יחיו מתיך מתים שבא"י נבלתי יקומון מתים שבחוץ לארץ ומאי ונתתי צבי בארץ חיים אנבוכד נצר הוא דכתיב דאמר רחמנא מייתינא עלייהו מלכא דקליל כי טביא
Rabbi Abba bar Memel raised an objection from a different verse: “Your dead shall live; my dead bodies shall arise” (Isaiah 26:19). What, is it not the case that the phrase “Your dead shall live” is referring to the dead of Eretz Yisrael, whereas the subsequent phrase “My dead bodies shall arise” is referring to the dead of the lands outside of Eretz Yisrael? And if so, what is the meaning of the verse “And I will set glory [tzvi] in the land of the living”? This verse is written with regard to Nebuchadnezzar, as the Merciful One states: I will bring upon you a king who is as swift as a deer [tzvi].
And more recently:
or again more clearly:After Rabbi Eliezer’s opinion that He made them swear by heaven and earth, the Midrash brings Rabbi Chanina’s opinion, that He made them swear by the Patriarchs and Matriarchs, and Rabbi Yehuda’s opinion, that He made them swear by circumcision. Then comes the Rabbis’ opinion: He made them swear by the Generation of Martyrdom. “By the tzvaos” – they did My will (tzivyoni) in the world, and I did My will with them. “Or by the deer of the fields” – they pour out their blood for the sanctification of My name like the blood of the gazelle and the blood of the deer. This is the meaning of the verse, “For on Your account we were killed all day long; we were considered like sheep to be slaughtered” (Tehillim 44:23).http://www.truetorahjews.org/maharal
I think the term 'Ebionites' (misunderstood because of misreading of a tsadi for an alef) = (tz)ivyoni goes back to a primitive class of Jewish Christian martyrs who like Jesus embodied 'God's will' on earth - cf. 'thy will be done as it is on earth as it is in heaven'With what did He make them swear? Rabbi Eliezer says: He made them swear by heaven and earth and by the animals of the field… Rabbi Chanina says: He made them swear by the Patriarchs, the Matriarchs and the Twelve Tribes… Rabbi Yehuda says: He made them swear by circumcision… The Rabbis say: He made them swear by the Generation of Martyrdom. “By the tzvaos (lit. gazelles)” – they did My will (tzivyoni) in the world, and I did My will with them. “Or by the deer of the fields” – they pour out their blood for the sanctification of My name like the blood of the gazelle and the blood of the deer. This is the meaning of the verse, “For on Your account we were killed all day long; we were considered like sheep to be slaughtered” (Tehillim 44:23). Rabbi Chiya bar Abba said: If someone were to say to me, give your life for the sanctification of the name of the Holy One, blessed is He, I would give it, but only if they would kill me quickly. But in the Generation of Martyrdom I would not be able to withstand the trial. What did they do in the Generation of Martyrdom? They brought balls of iron, made them white-hot in the fire and placed them under their armpits and burned their souls out of them. And they brought shells of reeds and placed them under their nails and burned their souls out of them.http://www.truetorahjews.org/siman20