Sigh. As soon as I saw the topic, I could guess what some of the responses would be.
Whenever this question comes up, someone says that Judaism in Hellenistic/Roman times *did* seek converts and someone else says, No, they didn't. And neither side seems to realize how much disagreement there has been among historians on this issue.
I'll quote a couple of old old soc.history.what-if posts of mine:
***
There has been considerable debate among historians as to the extent to
which Jews of the Hellenistic and Roman ages *did* in fact seek converts.
I am no expert in this field, but I thought it might be interesting to
summarize the arguments of two historians with contrasting views: Martin
Goodman, *Mission and Conversion: Proselytizing in the Religious History
of the Roman Empire* (Oxford: Clarendon Press 1994) and Louis H. Feldman,
*Jew and Gentile in the Ancient World: Attitudes and Interactions from
Alexander to Justinian* (Princeton, NJ: Princeton University Press 1993).
To begin with their *conclusions*:
(1) Feldman: "Finally, although McKnight [a historian who agrees with
Goodman] is ready to admit that the Jews during this period almost
universally approved of proselytes and ecnouraged them to join the Jewish
fold, he argues vehemently that this does not constitute evidence that they
engaged in missionary activity among Gentiles. However, although there is
in truth, no single item of conclusive evidence, the cumulative evidence--
both demographic and literary--for such activity is considerable." (pp.
292-3)
(2) Goodman: "Since the work of Schurer and Juster at the beginning of
this century, most scholars have subscribed to the view that Jewish
proselytizing in antiquity reached a peak of intensity in the first century
of the Christian era at the time of the emergence of Christianity...I hope
to show in this chapter the flimsiness of the hypothesis on which the
mainstream consensus is based.
"I should make it clear that I do not doubt either that Jews firmly
believed in their role as religious mentors of the gentile world (so Wisdom
of Solomon 18: 4) or that Jews expected that in the last days the gentiles
would in fact come to recognize the glory of God and divine rule on earth
(cf. Isa. 66: 19; 2 Baruch 68: 5). But the desire to encourage admiration
of the Jewish way of life or respect for the Jewish God (that is,
apologetic mission) (cf Psalam 117) or to inculcate general ethical
behaviour in other peoples (educational mission), or pious hope for the
possibly distant eschatological future, should be clearly distinguished
from an impulse to draw non-Jews into Judaism in the present." (pp. 60-61)
"Before 100 CE Jews accepted as proselytes those gentiles who applied to
join their number but they did not feel impelled to encourage such
conversions." (p. 129)
***
Unfortunately, I don't have Feldman's or Goodman's books right now, and I
never went beyond summarizing their *conclusions* (as above) when this
subject came up here a while back. I did however cite Feldman's summary of
his "demographic evidence" (p. 293 of his book):
"3. The Demographic Evidence for Missionary Activity
"The Jewish attitude toward proselytism apparently changed from a passive
to a more active approach during the Hellenistic period. The chief reason
for presuming that there were massive conversions to Judaism during this
period is the seemingly dramatic increase in Jewish population at this
time. Preexilic Judaea (which contained the major part of the Jewish
population at the time of the destruction of the First Temple in 586
B.C.E.), according to Baron's calculations [referring to Salo W. Baron's
article on "Population" in Encyclopedia Judaica], based on biblical and
archaeological data, had no more than 150,000 Jews. By the middle of the
first century C.E. he estimates that the total number of Jews inthe world
had risen to about eight million and that the Jews constituted about one-
eighth of the population of the Roman Empire. Even if we accept Harnack's
minimum estimate, there were four million Jews in the empire. True, some
of the increase can be accounted for by the Jews' superior hygiene (the
incidental result of legislation both in the written and in the oral Torah)
and their refusal to practice birth control, abortion, or infanticide (see
Tacitus, *Histories* 5.5.3) True also, the expansion and intensification
of agriculture in Ptolemaic Egypt succeeded in yielding food to a degree
unrivaled until a century ago, so that a larger population generally, at
any rate in Egypt, could be supported; but the figures demand further
explanation. Only prosyletism can account for this vast increase, though
admittedly aggressive prosyletism is only one possible explanation for the
numerous conversions."
***
All I'll add right now to these posts is (1) a review of Goodman at
http://bmcr.brynmawr.edu/1995/95.01.03.html
and (2) "Winning the Gentiles", chapter one of John Dickson's *Mission-Commitment in Ancient Judaism and in the Pauline Communities*
http://www.johndickson.org/uploads/2/3/8/8/23884833/missioncommitment_chap1.pdf "The question of whether Judaism at the time of Christian origins was a ‘missionary religion’ is a well-worn track in scholarship and, as yet, no consensus has been reached." In a footnote, he summarizes who takes which side:
"Those who affirm the presence of ‘mission’ in ancient Judaism include: Bamberger,
B. J. Proselytism in the Talmudic Period. New York: Ktav Publishing House, 1968;
Braude, W. G. Jewish Proselytizing in the First Five Centuries of the Common Era: the
Age of Tannaim and Amoraim. Providence, R.I.: Brown University Press, 1940; Kasting,
H. Die Anfänge der urchristlichen Mission: Eine historische Untersuchung. BEvT, 55.
Munich: Chr. Kaiser Verlag, 1969; Moore, G. F. Judaism in the First Centuries of the
Christian Era: the Age of the Tannaim. Vol. 1. Cambridge: Harvard University Press,
1932; Feldman, L. Jew and Gentile in the Ancient World. Princeton: Princeton University
Press, 1993, 288-415; Feldman, L. H. “Jewish Proselytism.” In Eusebius, Christianity,
and Judaism, edited by H. W. Attridge and G. Hata. Detroit: Wayne State University
Press, 1994; Harnack, A. D. The Mission and Expansion of Christianity in the First Three
Centuries. 2 vols. Vol. 1. London, 1908; Nock, A. D. Conversion: the Old and the New
in Religion from Alexander the Great to Augustine of Hippo. Oxford: Clarendon Press,
1933; Jeremias, J. Jesus' Promise to the Nations. London: SCM Press, 1958, 11-19;
Georgi, D. “Missionary Activity in New Testament Times.” In The Opponents of Paul in
Second Corinthians, 83-228. Edinburgh: T & T Clark, 1987; Carleton Paget, J. “Jewish
Proselytism at the Time of Christian Origins: Chimera or Reality?” JSNT 62
(1996): 65-103; Borgen, P. “Proselytes, Conquest, and Mission.” In Recruitment,
Conquest, and Conflict: Strategies in Judaism, Early Christianity, and the Greco-Roman
World, edited by P. Borgen, 57-77. Atlanta: Scholars Press, 1998; Segal, A. F. “The
Costs of Proselytism and Conversion.” In Society of Biblical Literature 1988 Seminar
Papers, edited by David J. Lull, 336-69. Atlanta: Scholars Press, 1988; Bedell, C. H.
“Mission in Intertestamental Judaism.” In Mission in the New Testament: An Evangelical
Approach, edited by W. J. Larkin and J. F. Williams, 21-29. Maryknoll N.Y.: Orbis
Books, 1998. Those who (variously) deny this thesis include: Munck, J. Paul and the
Salvation of Mankind. London: SCM, 1959, 264-271; McKnight, S. A Light Among the
Gentiles: Jewish Missionary Activity in the Second Temple Period. Minneapolis: Fortress
Press, 1991; Goodman, M. Mission and Conversion: Proselytizing in the Religious
History of the Roman Empire. Oxford: Clarendon, 1994; Collins, J. J. Between Athens
and Jerusalem: Jewish Identity in the Hellenistic Diaspora. Second ed, The Biblical
Resource Series. Grand Rapids: Eerdmans, 2000, 261-72; Riesner, R. “A Pre-Christian
Jewish Mission?” In The Mission of the Early Church to Jews and Gentiles, edited by J.
Ådna and H. Kvalbein, 211-50. Tübingen: Mohr Siebeck, 2000; Levinskaya, I. Diapora
Setting. The Book of Acts in its First Century Setting, Vol. 5. Grand Rapids: Eerdmans,
1996, 19-49; Cohen, S. J. D. “Was Judaism in Antiquity a Missionary Religion?” In
Jewish Assimilation, Acculturation, and Accomodation: Past Traditions, Current Issues
and Future Prospects, edited by M. Mor, 14-23. New York: University Press of America,
1992. However, Cohen does admit certain missionary tendencies on the part of many
ancient Jews and a desire to see the Gentiles converted. See also his article, Cohen, S. J.
D. “Conversion to Judaism in Historical Perspective: From Biblical Israel to Postbiblical
Judaism.” Conservative Judaism 36, no. 4 (1983): 31-45."