Kareem,
On first look at the first three Gospels, you are right, it does appear that the Crucifixion took place on the Friday of Holy Week. It's John's Gospel that shows more specific evidence of the events of the week than Matthew, Mark and Luke do, and indicate the specific days involved.
John 19:14 states "now it was the day of preparation (paraskeue) for the Passover;(tou Pascha) it was about the 6th hour. And he ( Pilate) said to the Jews "Behold your King".
To understand this passage properly you do need to look at the use of the word paraskeue as Aineo has suggested.
Paraskeue is used as a technical term for Friday, since every Friday, was the day of preparation for the Sabbath or Saturday. In modern Greek, the word for "friday" is Paraskeue.
Second, the Greek term for the passover is tou pascha, and is taken to be quivelent to the passover week. This refers to the seven day Feast of the Unleavened Bread (Hebrew Massot) that immediately followed the initial slaughter and eating of the passover lamb on the evening of the 14th day of the month of Habib, which by Hebrew reckoning would mean the commencement of the 15th day before sunset.
The week of massot coming right on the heels of Passover itself, very naturally became known as Passover week (Encyclopaedia Brittanica 14th edition, 12:1041). extending from the 15th to the 21st day of Habib inclusively.
Popular usage merged the two festivals and treated them as unity. So therefore, the literal translation of the as "the preparation of the passover" must in this context be rendered the Friday of the Passover week.
So, , yes Kareem, Jesus was crucified on the Friday. However, how then does this work, with the idea that he was dead for three days and nights as per the Scriptures?
The apparant contradiction of the timing of the death of christ is the key to this issue. Mark 15:25 states Jesus was crucified at the third hour on Friday and John 19:14 states that the trial was still going on at the sixth hour, indicating the crucifixion was later yet.
Either
1. One of the evangelists were in error
2. A text was miscopied at some stage in the manuscripts
or 3. The hours of the day have been numbered by John according to
a different system than that followed by Mark.
It should be noted that both Matthew and Luke follow the same system as Mark for all three indicate that as Jesus hang on the cross a terrible darkness came on the earth at the 6th hour and lasted till the 9th hour. when Jesus breathed His last.
It is universally agreed that the Matthew, Mark and Luke numbered the from sunrise at approximately 6:00am. This would mean that Christ was crucified at 9:00am and the prenatural darkness lasted from 12 noon until 3pm.
John however, used the official Roman numbering system. The evidence for a civil day that began numbering the hours right after midnight is quite decisive. Pliny the Elder (Natural history 2:77) makes the following observation.
"The day itself has been differently observed in different countries. By the babylonians, between two sunrises and by the Athenians, two sunsets, by the Umbrians from noon to noon and by Roman priests and those who have defined the civil day, as the Egyptians also and hippaarchus, from midnight to midnight. This is confirmed by Macrobius in Saturnalia 1:3 "the day, which the Romans have declared to begin at the 6th hour of the night." (it should be also understood that the ancients did not maintain hours of uniform length through out the year, but simply divided the interval between sunrise and sunset into 12 equal parts know as horae, regardless of the season of the year)
So, what would be 6:00am according to the Roman Civil day and also by our modern practise, would be the first hour according to Athenian and Hebrew practice. Thus it was 9:00am when the trial was finishing and He was led away to Golgatha to be crucified. This understanding of the numbering system, does away with all supposed discrepancies in the numbering systems, as it makes the time identical in all Gospels.
Now, if Jesus died at 3:00pm near the close of Friday (according to the Hebrew method of reckoning each day from sunset to sundown), this would be the first day ie Friday.
Then Friday 6:00pm - Saturday 6:00pm would be the second day and Saturday 6:00pm- Sunday 6:00pm would be the third day. (during which, ie Sunday at 6:00am or a little before) Jesus rose from the dead.
Why then are three portions of the day mentioned in Matthew 12:40 as three days and three nights? The simple answer is that the only way "day" in the sense of dawn to dusk sunlight could be distinguished from a 24 hour cyle sense of day, was to speak of the latter as a night and a day,. In other words, Friday had to begin on Thursday at 6:00pm and lasted until Friday at 6:00pm. Correspondingly, Sunday began at 6:00pm on Saturday night according to Hebrew reckoning. So Thursday night, was actually Friday the first night and day (even though Jesus was crucified during the day on Friday), Friday night was the second night and day and Saturday night was the third night and day (and Jesus rose on the morning of the Sunday at dawn).
According to ancient tradition, when you wished to refer to three separate 24 hour periods, you said "three days and three nights' even though only a portion of the first and third days might be involved.
This is common in the Bible and you can see a similar usage in 1 Samuael 30:12 where "he had not eaten bread for three days and three nights." which meant the day before yesterday.
So, yes, according to the way the ancients read the days.. Jesus was indeed dead from Friday to Sunday when he rose again, but according to Jewish day reckoning, He was dead three days and nights, numbering the days from Thursday night to Sunday night. Hope this clarifies at least some of the discussions and brings everyone together in their understanding of the numbering systems.