according to Jewish custom any part of a day, however small, is included as part of a full day.
1 "Since the Jews reckoned part of a day as a full day, the 'three days and three nights' could permit a Friday crucifixion."
2This phenomena is exemplified in scripture in the book of Esther. "Go, assemble all the Jews who are found in Susa, and fast for me; do not eat or drink for three days, night or day. I and my maidens also will fast in the same way," (
Esther 4:16 ). Then, in
Esther 5:1 it says, "Now it came about on the third day that Esther put on her royal robes and stood in the inner court of the king’s palace in front of the king’s rooms, and the king was sitting on his royal throne in the throne room, opposite the entrance to the palace." We can see that even though the three days and nights had not been completed, Esther went in to see the King on the third day even though she said to fast for three days and nights. We see that "on the third day" is equivalent to "after three days."
Additionally,
Mark 8:31 says, "And He began to teach them that the Son of Man must suffer many things and be rejected by the elders and the chief priests and the scribes, and be killed, and after three days rise again." Yet,
1 Cor. 15:4 says, "and that He was buried, and that He was raised on the third day according to the Scriptures." Also,
Luke 24:5-7, "and as the women were terrified and bowed their faces to the ground, the men said to them, 'Why do you seek the living One among the dead? He is not here, but He has risen. Remember how He spoke to you while He was still in Galilee, saying that the Son of Man must be delivered into the hands of sinful men, and be crucified, and the third day rise again.'" Here we can see that "after three days" is equivalent to mean "on the third day."
Therefore, we can see that because of the Jewish usage of counting any part of a day as the whole of the day, the term "three days and nights" is idiomatic and not literal.
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