Ben Israel's printer's mark Menasseh b en Israel's knowledge was extraordinary and extensive in the theological rather than the talmudic sphere. This, together with his linguistic abilities, enabled him to present Judaism in an accessible and sympathetic manner acceptable to the Christian scholarly world. In this respect, he was a forerunner of the Jewish scholars of the 19th century. Ben Israel founded the earliest Hebrew printing press in Amsterdam (1626), where he published works in Hebrew, Spanish and Portuguese until the end of his life. Penei Rabbah, his index to the Midrashim, appeared in 1628. It was the first part of his Conciliador (1632, in Spanish; afterward in Latin; the final three parts appeared in Spanish only, 1641-51), which reconciled apparently discordant biblical passages which earned him a great reputation in Christian circles. Menasseh ben Israel Etching by Rembrandt Conciliador was followed by a series of works also largely directed to non-Jews: De Creatione (1635, Latin only); De Termino Vitae (1634, Latin only); De Resurrectione Mortuorum (1636); and De Fragilitate Humana (1642). Beside other minor works, he produced Thesouro dos Dinim, a code of Jewish law for returned Marranos (1645-47); La Piedra Gloriosa (1655); and Nishmat Hayyim (1651) on the nature of the soul. For these works, as well as his synagogue sermons, at which gentile scholars and notables were often present, he was regarded in the world of scholarship as the leading representative of Hebrew learning. The two greatest of his contemporary countrymen, Hugo Grotius (Dutch jurist and humanist) and Rembrandt, were among his admirers. Rembrandt painted and engraved a portrait of Ben Israel, as well as four etchings for the latter's mystical work, La Piedra Gloriosa..