This article sets out to re-examine Hebrew sources in the doctrine of the law of nations of the 17th century, from Gentili s De Jure Belli Libri Tres (although it strictly belongs to the 16th century since it was first published in 1598) to Pufendorf s De Jure Naturae et Gentium (1672). It incontrovertibly confirms the importance of Jewish sources in the general intellectual education of the founding fathers of international law and in their general political philosophy while limiting their role with respect to the construction of international law in the strict and contemporaneous sense of the term.