We are not the first Jews to live with enormous uncertainty about the future. Uncertainty, however, can be both paralyzing and liberating.When the Jewish people have great leadership, times of great uncertainty have become times of opportunity and transformation.The biblical narrative we read this week (Numbers 13:1-15:41) tells a dramatic story about the scouts sent to explore the Land of Israel before Joshua led the Israelites as they returned to their homeland. It was also a time of great uncertainty, and a time that called for brave leadership and ethical sensitivity. Was it too dangerous to return to the Promised Land? Was it an impossible dream? But what defines great leadership? Experts may disagree, but some of the greatest models of the theories they teach can be found in Jewish leadership. Throughout Jewish history, from the Exodus until today, Jewish leaders model – especially in times of crisis – some of the core aspects of effective leadership taught today, harnessing the power of Judaism and the Jewish people in order to protect. But how did they do it? What leadership skills do they share? A brief examination of three models: from the biblical Moses, to the sage Rabbi Yohanan Ben Zakai and then Theodor Herzl, reveals five key elements of effective leadership: (1) they were experts in their field; (2) they understood the challenges their people were facing from multiple perspectives; (3) they had built community and trust; (4) they were willing to take risks; and (5) they were motivated by ethical imperatives: to save the Jewish people.These three models couldn’t have lived in more different times, or have faced bigger crises.Moses (circa 1250 BCE) led the liberation of the Israelites from generations of slavery, and led them toward revelation at Sinai and the Promised Land of Israel. Ben Zakai (first century) led the transformation of Judaism after the destruction of the Second Temple; Herzl (1860-1904) conceived and then led the Zionist movement to the creation of a Jewish state. He sought to find an answer to the Jewish problem of suffering and oppression with the possibilities modern nationalism.In very different contexts, each of these leaders – a prophet, a rabbi and a politician – embodied not only powerful leadership capacities, but were guided by ethical imperatives and were willing to take risks.According to the Book of Exodus, Moses was nearly assassinated on several occasions: after he struck the Egyptian oppressor, and upon leading the Israelites fleeing for freedom across the Red Sea while pursued by the Egyptian army. Along the way he repeatedly faced the dangerous fury of God, of multiple enemies and of his own people. He risked everything on more than one occasion. Moses’s success is the basis of the ethical imperatives that should guide the Jewish people today.Similar arguments can be made about Ben Zakai, in fleeing the siege of Jerusalem in 68 CE and setting up the rabbinic academy of Yavne, and about Herzl, in calling for the Jewish state in 1896, expanding the Zionist movement, and establishing international alliances. Without each of these three giants of Jewish history we would probably still be enslaved – without Torah, without rabbinic tradition and without even the possibility of political sovereignty. In other words, we wouldn’t exist.While the existential threats of our time are real, we live with the blessing of Jewish sovereignty and the political leadership willing to take risks to defend the physical existence of the Jewish people.In our time, we still can and should learn from these models of great Jewish leaders who transformed societies – and history itself – because of their desire and capacity to act on ethical imperatives. We have been driven by God’s call to us to be not only free, but to be holy – to be ethically good (Leviticus 19:2).According to leadership experts, success in such a role depends upon the combination of knowledge, the trust of a community of people, the capacity to leverage power and the willingness to take risks. Successful leaders also learn from other leaders, from their brilliant successes and their disastrous mistakes.The challenges of our time are also filled with opportunity to find expanding ways of responding to God’s call that we be an Am Kadosh, a Holy Nation (Leviticus 19). But our holiness only matters if we can be both free and good, requiring leaders attuned to the sacred call and the needs of our time.Whether our leaders today have these leadership capacities and the willingness to take great risks for the sake of our collective ethical future remains to be seen. But if we fail, it won’t be because we lacked the knowledge, skill or inspiration. The writer is a rabbi and PhD, is the national director of recruitment and admissions and President’s Scholar at the Hebrew Union College-Jewish Institute of Religion, and teaches at the Shalom Hartman Institute.