Did Jesus die on Good Friday?

Matthias Grunewald, Isenheim Altarpiece, 1512-1516

I have been questioned (a lot) on Twitter by a tweep called @theTRUTHSPIRIT about Easter. The suggestion is that it is a Pagan festival and that Jesus didn't rise on Sunday. This is a question about Mass really. Catholics go to Mass on Sunday, but the Sabbath (or Shabbat) is celebrated Friday to Saturday.

To be precise, according to halakha, Shabbat is observed from a few minutes before sunset on Friday evening until the appearance of three stars in the sky on Saturday night. Shabbat is ushered in by lighting candles and reciting a blessing. Traditionally, three festive meals are eaten; on Friday night, Saturday morning, and late Saturday afternoon. Friday night dinner begins with kiddush and a blessing recited over two loaves of challah. Shabbat is a festive day when Jews are freed from the regular labours of everyday life. It offers an opportunity to contemplate the spiritual aspects of life and spend time with family.

The ancient Jews reckoned days from sundown to sundown, meaning that for them the first part of the day was evening. This is why Genesis 1 says things like, "And there was evening, and there was morning--the first day" (Gn 1:5). The same custom was observed by the ancient Phoenicians, Athenians, Arabs, Germans, and Gauls. Today Jews and other groups who keep the sabbath, such as the Seventh-Day Adventists, continue to celebrate it from sundown Friday to sundown Saturday. This way of reckoning time was not the only one in the ancient world. For example, the Romans reckoned days from midnight to midnight--the system we use today.

Christians also observe a day of rest, but have transferred the day to Sunday, which Tradition holds to be the day of the Resurrection. I suppose one of the first things to consider is that the majority of first Christians were Jews. They would have observed the Shabbat and then gone to their Christian celebration the day after.

Sunday is often spoken of as "the Christian sabbath," but this is not a technical description. Sunday is not a strict replacement for the sabbath (which has been abolished), but a day the Church instituted to fulfil a parallel function. Thus Ignatius of Antioch, the earliest Church Father to address this question, states that Christian converts "have given up keeping the sabbath and now order their lives by the Lord's Day instead, the day when life first dawned for us, thanks to him [Christ] and his death" (Letter to the Magnesians 9 [A.D. 107]).

Now, I hear you scream, Jesus did not come to abolish the Law, but to fulfil it! (Mt 5:17).

Absolutely, but the Mosaic Law had a specific purpose for the Children of Israel. The Law of the Old Testament consisted of both the moral law and the civil law. The moral law dealt with the great ethics of life. Its purpose was to set apart the chosen people of Israel from all other nations on the basis of inner holiness with regard to honour for both God and man. You have to remember that at the time, strength was the power that ruled all. One of the most extraordinary truths of biblical faith is that monotheism lifted the Israelites out of that melee for power and set them apart from other nations who’s basis was strength and domination. This great moral law was to uplift the Children of Israel to a much higher standard of holiness and to serve as a model for all people of all generations (Isaiah 42:6). For example, the Ten Commandments are a code of moral law that pertain to man's duties to God and fellow man. They are laws unaffected by changes in the environment, and thus themselves remain unchanged.

The civil law was different. It consisted of rules and regulations that pertained to everyday living; and these rules were influenced by both environment and customs of neighbouring pagan communities. Such laws dealt with issues of cleanliness, food, health, clothing, and religious ritual. The purpose of these laws was to set apart the Children of Israel from all other nations on the basis of outer holiness. They were to remain separate and distinct, and were to be distinguished in the eyes of the rest of the world for serving the one true God, and refusing to adopt the practices and superstitions of idolatrous worship that surrounded them.
Among these civil laws was the rule that forbade the eating of pig meat. It was a common practice among neighbouring pagan tribes to offer a pig as a sacred sacrifice to their idols. Furthermore, in that time and in that part of the world, the pig was a very filthy animal that fed on dead meat and rubbish. As a result, eating pork caused the spread of terrible diseases that affected the whole community. This law made perfect sense, like the law about shellfish, which we all know can give you a very dodgy tummy if it is not fresh!

Traditionally we have understood that the OT Law contains elements that are indicative of God's unchanging character, and therefore do not pass away with the coming of the Messiah. Indeed the NT reiterates their significance. (e.g. the Ten Commandments). There are elements in the Levitical law that Jesus fulfils, and therefore we have no further need of them (e.g. the sacrificial system), and there are elements that are distinctive to the society of Israel at the time, that may contain some wisdom for us, but are not applicable in the society in which we live, such as the kinds of things you reference. If we only had the OT to go on for developing a view of the homosexual lifestyle vis-à-vis appropriateness for Christians, we would have theological difficulties sustaining prohibition.

With regard to the second part of @theTRUTHSPIRIT's question, the dilemma really is this: in the narrations of the evangelists, there is an apparent contradiction Between the Gospel of John, on the one hand, and what, on the other hand, Matthew, Mark, and Luke tell us. According to John, Jesus died on the cross precisely at the moment in which, in the Temple, the Passover lambs were being sacrificed. His death and the sacrifice of the lambs coincided. This means that He must have died the day before Easter and that, therefore, he could not have personally celebrated the paschal supper; at least that is what it would seem.

On the contrary, according to the three synoptic evangelists, the Last Supper of Jesus was a paschal supper, in its traditional form. He introduced the innovation of the gift of his body and blood. This contradiction, until a few years ago, seemed impossible to resolve . . .

The discovery of the manuscripts of Qumran has led us to a convincing possible solution that while not accepted by all, is highly probable. We can now say that what John referred to is historically correct. Jesus truly spilled his blood on the eve of Passover at the hour of the sacrifice of the lambs. However, he celebrated Passover with his disciples probably according to the calendar of Qumran, that is to say, at least one day earlier —he celebrated without a lamb, like the Qumran community who did not recognise the Temple of Herod and who was waiting for a new temple.

"the day of preparation," in the Gospels, speaks in accord with the way the Passover was celebrated in the temple and by the priests. Though a strict observance of the date of Passover would have had "the day of preparation" to be on Thursday, the fourteenth of Nisan, the common practice of the day was similar to modern practice in the Church. Feasts could be, and often were, moved to the closest Sabbath. Thus, "the day of preparation," when the lambs were actually slain would have been Friday, rather than Thursday. Thus, Christ would have been crucified on Friday, "the day of preparation" (cf. Matt. 27:62).

You might wonder then how the apostles could have celebrated the Passover if there were no sacrificed lambs to use for the liturgical observance. The Qumran dimension noted above gives a very plausible, though not definitive, answer to that question. It argues that Jesus celebrated the Passover without a lamb—instead of which he gave himself, his body and his blood.

Understanding that Easter begins with the vigil on Holy Saturday, "the day before Easter" would refer to Friday, not Thursday. The traditional day of Good Friday to be the day Jesus was crucified.

Easter

With regard to Easter itself, it is interesting to note that in Italian the word Pasqua, which means Easter. The Italian word for Passover is Pesach. The English word Easter, comes from the Old English: Ēostre and was also known as the Pasch. Among Eastern Orthodox it is known as Pascha (Latin: Pascha; Greek: Πάσχα, Paskha; Aramaic: פַּסחא‎ Pasḥa; from Hebrew: פֶּסַח‎ Pesaḥ). Easter is linked to the Jewish Passover by much of its symbolism, as well as by its position in the calendar. In many languages, the words for "Easter" and "Passover" are etymologically related or homonymous. The second century equivalent of Easter and the Paschal Triduum was called by both Greek and Latin writers "Pascha (πάσχα)", a Greek transliteration of the Aramaic form of the Hebrew פֶּסַח, the Passover feast of Exodus 12. Paul writes from Ephesus that "Christ our Pascha has been sacrificed for us," although the Ephesian Christians were not the first to hear that Exodus 12 spoke about the death of Jesus. In most of the non-English speaking world, the feast today is known by the name Pascha and words derived from it.

The modern English term Easter developed from the Old English word Ēastre or Ēostre, which itself developed prior to 899, originally referring to the name of the Anglo-Saxon goddess Ēostre. Bede notes that the native Old English month Ēostur-monath (Old English "Ēostre-month") was equivalent to the month of April, yet that feasts held in the goddess's honour during Ēostur-monath had gone out of use by the time of his writing and had been replaced with the Christian custom of the "Paschal season". The feast was also historically referred to in English as "Pash" or "Pace", from the Latin pascha.

This is consistent with the way in which the Church Christianised Pagan festivals, organically including them in the Church's liturgy and worship. The first Christians, Jewish and Gentile, were certainly aware of the Hebrew calendar (Acts 2:1; 12:3; 20:6; 27:9; 1 Cor 16:8), but there is no direct evidence that they celebrated any specifically Christian annual festivals. Direct evidence for the Easter festival begins to appear in the mid-2nd century. Perhaps the earliest extant primary source referencing Easter is a mid-2nd century Paschal homily attributed to Melito of Sardis, which characterises the celebration as a well-established one. Evidence for another kind of annual Christian festival, the commemoration of martyrs, begins to appear at about the same time as evidence for the celebration of Easter. But while martyrs' days (usually the individual dates of martyrdom) were celebrated on fixed dates in the local solar calendar, the date of Easter was fixed by means of the local Jewish lunisolar calendar. This is consistent with the celebration of Easter having entered Christianity during its earliest, Jewish period, but does not leave the question free of doubt.

The ecclesiastical historian Socrates Scholasticus (b. 380) attributes the observance of Easter by the church to the perpetuation of its custom, "just as many other customs have been established," stating that neither Jesus nor his Apostles enjoined the keeping of this or any other festival. Although he describes the details of the Easter celebration as deriving from local custom, he insists the feast itself is universally observed.