Noted writer and rationalist; born at Oporto, 1590; died at Amsterdam, April, 1647. Born and reared in a Marano family, all of whose members had become strict Catholics—his father held an ecclesiastical position—young Gabriel seems to have pondered secretly on the race and faith of his fathers, to which he felt himself powerfully attracted. When apprenticed to the legal profession he found time to study the Law and the Prophets, and he experienced the influence of their broad humanitarian views and of their noble conceptions of the Deity. Dissatisfaction with the formal routine of Catholicism was probably responsible for his spiritual uneasiness, as suggested by Grätz ("Gesch. d. Juden," 10:133). In 1615 force of circumstances compelled him to accept the semi-legal, semi-clerical office of treasurer of an endowed church in Oporto: his father being dead, the support of his mother and young sister and brothers devolved upon him. Cautiously revealing to these relatives his heart's longing for Judaism, he found them acquiescent; and in 1617 or 1618, after running great danger of detection and punishment, the family emigrated from Portugal to Amsterdam, where they could openly live as Jews. In Amsterdam they abjured Christianity; and Gabriel and his four brothers (Kayserling, "Gesch. d. Juden in Portugal," p. 287) entered the Abrahamic covenant, Gabriel discarding his name for Uriel.
Full of enthusiasm for Judaism—an enthusiasm that had fed upon his dreams and fancies of the unknown faith and the bygone history of his people—it was almost in the nature of things that Acosta should be doomed to suffer severe disenchantment through the realities he encountered. The days of Moses and Isaiah no longer existed: in place of their broad principles and declarations he found in the Judaism of Amsterdam a rigid, cumbersome, and prosaic accumulation of ritual and observance, "line upon line, and precept upon precept." This was very different from the free and liberal religion which his inexperienced fancy had pictured to him in his native land. Feeling the inspiration of his high ideals, he was frank enough to express outspokenly his disgust with the formal Judaism of the day. Something of his Christian training may have shaped his phraseology when he openly spoke against "the Pharisees" of the Amsterdam synagogue; but he naturally knew nothing of the fierce heat of suffering which had fused the faith of Isaiah, and welded it into the rigid forms he found extant. On their side the Amsterdam Jews, who had known persecution and were grateful even for the tacit tolerance of the Netherlands, were not disposed calmly to see an impetuous and ill-informed young enthusiast openly assail the ancestral faith. By his criticisms against Judaism, Acosta thus condemned himself to a life of severe isolation almost from the hour of his arrival in Amsterdam. When it got abroad that he was preparing a book which should set forth his grave doubts as to the immortality of the soul and the reality of future reward or punishment, and should, moreover, point out the discrepancies between the Bible and rabbinical Judaism—soundly rating the latter for its accumulation of mechanical ceremonies and physical observances in lieu of spiritual maxims and philosophic conceptions—he was answered even before he had spoken, as it were, by the publication of a work in Portuguese, written by a certain physician, Samuel da Silva, in 1623, "Tratado da Immortalidade da Alma, Composto pelo Doutor! . . . em que Tambem se Mostra a Ignorancia de Certo Contrariador," etc. But this only served to expedite Acosta's work, which appeared in 1624, also in Portuguese, under the title "Examen dos Tradiçoens Phariseas Conferidas con a Ley Escrita por Uriel, Jurista Hebreo, com Reposta a hum Semuel da Silva, seu Falso Calumniador." Acosta's lack of clearness, either of expression or of thought, or of both, is shown by the fact that in this work he reiterates that the soul of man is not immortal—the very heresy of which Da Silva had accused him.
The matter had now become so public that the officials of the Amsterdam Jewish community could not but take notice of it. Accordingly, Acosta was indicted before the magistracy for the utterance of views subversive of the foundations not only of Jewish, but of Christian, faith; and judgment wasasked against him as a public enemy to religion. He was arrested, thrown into prison, and fined 300 gulden ($120); and his book was condemned to be publicly burned. Acosta seems to have fled to Hamburg after this (see Perles, in "Monatsschrift," 1877, p. 206), but he eventually returned; for doubtless he felt himself completely ostracized there too by Jew and Christian alike. Moreover, he was ignorant of the German language. He returned to Amsterdam in bitter resentment. He found he could not live in seclusion; he yearned for companionship; he desired to marry again—he seems to have lost his wife in the interim (see Perles, c., p. 209)—and as the guardian of his younger brothers he feared their financial interests would suffer through his disgrace. Accordingly, he resolved to swallow the bitter draft. He volunteered, as he says, "to become an ape among the apes," and in 1633 he offered his formal submission to the officers of the synagogue; he would be a dissenter and a sinner no more.
Though outwardly obedient, Acosta's enthusiastic religious bent had evolved a new tendency away from Judaism. "I doubted whether Moses' law was in reality God's law, and decided that it was of human origin, as many others in the world have been." One step led to another. A species of natural religion, free from form or formula, bereft of all ceremony and ritual, seemed to him to be the true religion for man. He became a Deist. God is in nature the ruler of the external world: He has no concern with doctrines or modes of worship, all of which are equally vain in His sight. Nature teaches peace and harmony: religion uses the sword or the stake, or else the ban of excommunication. All the religion he would approve is contained in the seven Noahidic commandments ("Exemplar Humanæ Vitæ," ed. Limborch, p. 666).
Unfortunately for himself, Acosta could not be a perfect hypocrite: in his mode of life he continually transgressed Mosaic and rabbinical regulations, such as those touching the Sabbaths and festivals, the dietary laws, etc.; and people soon knew of it. His own relatives severely condemned him for this unfaithfulness, but to no purpose. Finally it was learned that he had dissuaded two Christians—a Spaniard and an Italian—from carrying out their avowed intention of embracing the religion of Israel; and this treachery, as it seemed, once more brought the lightnings of authoritative Judaism about his head. Summoned again before the officials of the congregation, he was required to renounce the errors of his way under penalty of the "greater ban." He would not submit; and again he was excommunicated. This further stroke of bigotry, as he considered it, was borne by him in sullen silence for seven years, during which time he suffered the indignity of being avoided by all, even by his nearest relatives. At the end of that period he succumbed and once more gave in his submission to authority, and was made to testify to it by the most degrading penances. Before the assembled hundreds in the synagogue—men and women—he recited a public confession of his sin and a recantation; this was followed by a public scourging then and there, to the extent of the Biblical "forty stripes save one"; and as the crowning act he was laid prostrate upon the threshold of the holy place, to be stepped over or trampled on by the gathered crowds. A proud and indomitable spirit like Acosta's might submit outwardly to such terrible formalities; but it could not brook them tamely. He went home, and shortly after ended his stormy career by shooting himself, having used the interval to write a few pages of what he called "Exemplar Humanæ Vitæ" (A Specimen of Human Life), a sketch of his own career. It is almost the only source of information respecting the life of this eccentric and unfortunate thinker, and was published with a refutation by Philip Limborch, a Dutch theologian, as an appendix to his own work, entitled "Amica Collatio cum Erudito Judæo," Gouda, 1687; republished 1847.
The "Exemplar Humanæ Vitæ," even making allowance for the intense mental stress under which it was written, and for the natural temptation to leave behind as crushing an indictment of his opponents as he could frame, shows Acosta to have been an ill-balanced thinker, impulsive to a degree, impatient, and presumptuous in the face of grave disabilities. Had careful religious training in Judaism been joined to more wisely directed energies, the uncommon intellectual endowments he undoubtedly possessed might have made of him a powerful champion of the ancestral faith, a "Pharisee of the Pharisees." He had all the superabundant zeal necessary for the equipment of such a defender of the faith.
An interesting reference to Acosta was discovered (see Perles, in "Monatsschrift," 1877, 26:193) in a letter printed in a volume of responsa by a certain learned Venetian merchant, Jacob b. Israel ha-Levi (2d ed., Venice, 1632, art. 49). In this letter, advice is asked of Ha-Levi as to the propriety of interring in the congregational cemetery the mother of an unnamed renegade, who had herself shared in her son's apostasy. The description given of the unnamed apostate's acts and writings, as well as the date of the letter and the known literary correspondence of the Amsterdam ecclesiastical authorities with Ha-Levi, leaves no room for doubt that Acosta was the excommunicate in question.
The tragic life of Acosta has furnished material for the dramatist and the novelist. The most important dramatic production is Gutzkow's tragedy, entitled "Uriel Acosta" (Leipsic, 1847), translated into Hebrew by Solomon Rubin, Vienna, 1856. The novelist Zangwill has also used the material for a sketch in his "Dreamers of the Ghetto" (pp. 68-114, Philadelphia; 1898).