This paper focuses on competing explanations of childbearing behaviour among Jews in Israel. Despite evidence of the second demographic transition in Israel, total fertility has not declined during the last three decades, unlike in most western high-income democracies. Two alternative explanations in the literature address this phenomenon. One is religiosity and the other is a nationalist sentiment at the aggregate level -both driving the high fertility rates. Using structural equation modelling, the current study tests the association of each of these two factors with fertility. Religiosity and nationalism were constructed as latent variables based on individual-level observed measures. Supporting previous studies at the aggregate level, the current analysis confirms that religiosity is the main determinant of fertility at the individual level, whereas nationalism has an effect on fertility only due to its high connection with religiosity. Parsimonious and comprehensive models of Jewish fertility in Israel and further research directions are suggested.