Etymology

From PIE *bʰeydʰ-: to compel, to force; to trust. (*bʰeydʰ-ti-s > πίστις).

Hence *bʰeydʰ-os: πειθός, fidus, fœdus; *bʰéydʰeti (tematic root): whence fido (>fides ➚): trust; πείθω: persuade and πείθομαι: be persuaded, obey, trust. Related to πίστευσις, πεῖσις, ἀπιστέω, πιστός/ἄπιστος, πιθανός and specially to πιστεύω: trust, put faith in, rely on; believe, feel confident.

Uses

The word πίστις appears for the first time in Hesiod’s Works and Days: πίστεις γάρ τοι ὁμῶς καὶ ἀπιστίαι ὤλεσαν ἄνδρας, “for in fact, trust and distrust destroy men equally” (Hes. WD 372). The word is also attested in Theognis: πίστει χρήματ’ὄλεσσα, ἀπιστίηι δ’ἐσάωσα· γνώμη δ’ἀργαλέη γίνεται ἀμφοτέρων, “through trust I lost my possessions, through distrust I rescued them; awareness of both brings bitterness.” (Thgn. 381). These are just two cases in Archaic Greece in which we can see the direct relationship of the term with the concepts of trust and credit between people.

Although these are the first written testimonies of our lemma, we already had back in Homer some previews of πίστις through forms that share the root (πιστός, πείθω, πιστόω…). In the fourth book of the Iliad, usually known as the Violation of the Oaths, the assembled gods debate the fate of Troy: Zeus thinks of ending the fight, but Hera does not want her work (having gathered the Achaean armies) to be in vain, and she prefers to see Priam and his sons fall. Zeus sends Athena to make the Teucrians break their oaths; she appears to Pandarus and persuades him to shoot an arrow at Menelaus. She deflects the arrow so that Menelaus is hit and wounded. Then, his brother Agamemnon, cursing the Trojans, worries about him and sends for a doctor, although he never forgets his pride.

Hom. Il. 4.155-159
φίλε κασίγνητε θάνατόν νύ τοι ὅρκιʼἔταμνον
οἶον προστήσας πρὸ Ἀχαιῶν Τρωσὶ μάχεσθαι,
ὥς σʼἔβαλον Τρῶες, κατὰ δʼὅρκια πιστὰ πάτησαν.
οὐ μέν πως ἅλιον πέλει ὅρκιον αἷμά τε ἀρνῶν
5σπονδαί τʼἄκρητοι καὶ δεξιαὶ ᾗς ἐπέπιθμεν.

Dear brother, it was for thy death, meseems, that I swore this oath with sacrifice,
setting thee forth alone before the face of the Achaeans to do battle with the Trojans,
seeing the Trojans have thus smitten thee, and trodden under foot the oaths of faith ^[*]Which would be more appropriately translated as oaths of loyalty..
Yet in no wise is an oath of none effect and the blood of lambs
and drink-offerings of unmixed wine and the hand-clasps, wherein we put our trust.

¡Hermano querido! Para tu muerte celebré el jurado convenio
cuando te puse delante de todos a fin de que lucharas por los aqueos, tú solo, con los troyanos.
Así te han herido: pisoteando los juramentos de fidelidad.
Pero no serán inútiles el pacto, la sangre de los corderos,
las libaciones de vino puro y el apretón de manos en que confiábamos.

Discussion

Eduard Fraenkel (1916) argued that the fundamental meaning of πίστις was not trust. He proposed that the commercial meanings of guarantee, security, and credit, as well as 'loyalty' in relationships, would have dominated the literature of the republic, whereas trust would not have been a weighty meaning until the early 1st century BCE. Gérard Freyburger, dispelling any doubts, re-established trust as the main value of πίστις/fides. The author stresses that trust implies two meanings: the trust one gives and the trust one receives (trust and trustworthiness).

Lately, the study of πίστις in the LXX and Hellenistic Judaism has flourished, motivated largely by interest in the roots of Christian faith. While recognizing that “faith”/“faithfulness” is not in Judaism the key concept that it is in Christianity, scholars have explored whether the Hebrew (emunah ➚) word translated by πίστις in the LXX (or with “faith” and “faithfulness” in modern languages) has similar meanings to those of πίστις in the NT, or whether it is different.

The starting point for all these discussions is the recognition that he'emin ➚ (the causative form of the Hebrew verb aman ➚, which is sometimes translated as 'have faith' or 'believe'), and its related noun emunah ➚ (often translated as 'faithfulness' or 'trustworthiness') are far from a perfect fit for πίστις. The root of this word in Hebrew also appears in words meaning 'wrap', 'carry', 'nurture', 'trust','firm', 'sure', 'reliable', 'dependable', 'steadfast', 'true', and scholars disagree about whether some of all these concepts carry over into the LXX and other Jewish uses of πίστις. In the LXX, πίστις is only used to translate this Hebrew word. Both ἀλήθεια and ἐλπίς are used to translate emunah ➚, while ἐλπίς is often closely associated with πίστις elsewhere in the Greek, πίστις and ἀλήθεια are less frequently found together. This suggests that in some passages the meanings of emunah ➚ may be quite divergent from those of πίστις. Thus, even when πίστις is used to translate emunah ➚, we cannot assume that it expresses the same concepts, relationships, or institutions as in non-Christian texts (Morgan 2015).

There is a great difference between the πίστις of the Greeks and the fides of the Romans. The Greek πίστις was between equals, for example, between nobles or between citizens, while the Roman fides was rather between unequals: victor and vanquished, Rome and the provinces, magistrate and citizen, patron and client, creditor and debtor (Momigliano 1987, 283).

Moreover, as Chantraine has explained, fides does not have the double value of πιστός, which can mean both "trusted" and "reliable," since the subjective or subject value predominates. Thus, fides est mihi does not mean "I am confident," but "one has confidence in me"; fidem habere alicui does not mean "to have confidence in someone," but "to attribute to someone the confidence that belongs to him" (Chantraine 1983, 74-76).

The conceptual change could not occur with the translation from Hebrew to Greek in the LXX. The translators of the LXX used in 31 passages the word πίστις to translate emunah ➚. On fewer occasions they used ἀλήθεια, "truth". They also translated on multiple occasions אֱמֶת, emet, by πίστις. Jerome, when translating the Vulgate from the Hebrew and Greek, always corrected the translators of the LXX in the cases of אֱמֶת, emet, ➚by using veritas, while on quite a few occasions when they used ἀλήθεια to translate emunah ➚, he corrected them by resorting to fides. In short, the translators of the LXX did not distinguish between אֱמוּנָה, emunah ➚, which had more closeness to πίστις/fides, and אֱמֶת, emot, ➚ which was closer to ἀλήθεια/veritas.This is a first cause of the conceptual change, since the scribes of the Church of Rome who wrote the Epistle to the Hebrews and the First Epistle of Clement to the Corinthians knew the wording of the Old Testament in Hebrew and Greek and were influenced by this conceptual confusion.

Now, why did the author of the Epistle to the Hebrews give πίστις this meaning instead of resorting to the Greek word for "belief," δόξα? Perhaps because δόξα has a less dogmatic sense, more akin to a simple opinion. Ancient religious thought admitted diversity of opinion when it came to such matters as the immortality of the soul (with Sadducees and Epicureans denying it, as opposed to Pharisees and Platonists, among others, affirming it; not that this meant that Sadducees and Epicureans did not believe in the existence of God or gods). Nor was the verb νομίζω, "to believe," useful, because it had nuances of reflexive character, such as "to consider" or "to think," which accommodated little to the dogmatic thinking that was trying to be imposed. Instead, πίστις could be used as the hif'il of the verb אָמַן, aman, "to confirm," because it meant "to believe" but firmly, with total certainty, or what is the same, not admitting other opinions. This kind of dogmatic thinking was emerging at the same time in the Pharisaic or rabbinic synagogues and in the Christian churches. It is no coincidence that at the same time that the Epistle to the Hebrews was written, the Sanhedrin of Yamnia promulgated the Birkat Ha Minim or Benediction against heretics, ordered by Gamaliel II and formulated by Rabbi Samuel, by which the Sadducees, the Nazarenes and, in general, all heretics were excluded from the rabbinical synagogues. The Christian concept of heresy emerged at the beginning of the second century in the Letters of Ignatius of Antioch and was developed in the second half of that century by Irenaeus of Lyon. The faith thus became a dogmatic thought that did not admit diversity of opinions and that condemned the heretic or heterodox, at first, to excommunication (the herem of the rabbis, but not the biblical herem) and, later, would act violently against them.

Analyzing the origins and evolution of fides ➚ and πίστις, it is observed that the meaning of the term "faith", understood as "system of religious beliefs", did not exist in classical times and did not spread until the Epistle to the Hebrews redefined πίστις in a theological sense. Its influence will be such that it will change the meaning of fides ➚ and emunah ➚ in their respective languages, creating a new conceptual category that will affect not only Christianity, in which it arises, but also Judaism and Islam. In the same way that the word religio ➚ did not allude in classical antiquity to any system of beliefs, but only to ritual or cultic practices, like the Greek word θρησκεία ➚ and the Hebrew word huqqat, the case of emunah/πίστις/fides ➚ must be considered in the perspective of the change of mentality that took place between ancient religious systems in which there were no dogmas and the practice of a certain cult allowed for different types of beliefs (such as those of the Sadducees, Pharisees and Essenes of pre-Christian Judaism) and the dogmatic religious systems that arose between the second and seventh centuries A.D., which were the result of the change of mentality that took place between the first and second centuries A.D. with religions such as Talmudic Judaism, Christianity and Islam.

Main sources

Homer - “Iliad” (8th century BCE)

Hesiod - “Works and Days” (7th century BCE)

Aeschylus - "The Persians" (525 - 455 BCE)

Sophocles - "Oedipus at Colonus" (497 - 406 BCE)

Herodotus - "Histories" (485 - 425 BCE)

Thucydides - "History of the Peloponnesian War" (460 - 400 BCE)

Lysias - "On a Wound by Premeditation" (458 - 380 BCE)

Plato - "Phaedrus" (428 - 348 BCE)

Aristotle - "Poetics" (384 BCE - 322 BCE)

Chrysippus - "Fragmenta Logica e Physica" (280 - 206 BCE)

Polybius - "Histories" (200 - 118 BCE)

Strabo - "Geography" (64 BCE - 23 CE)

Dionysius of Halicarnassus - "Roman Antiquities" (60 - 7 BCE)

Philo - "On the Creation" (20 BCE - 45 CE)

Flavius Josephus - "The Jewish War" (c. 20 BCE - c. 50 CE)

Clement of Rome - "First Epistle to the Corinthians" (1st century)

Pausanias - "Description of Greece" (110 - 180 CE)

Chariton of Aphrodesius - "Chaereas and Callirhoe" (1st-2nd century CE)

Galen - "Institutio Logica" (130 - 200 CE)