Testimony from both Jesus and the Apostles about when He rose:
Luke 24:46
Then He said to them, “Thus it is written, and thus it was necessary for the Christ to suffer and to rise from the dead the
third day,
Acts 10:40
Him God raised up on the
third day, and showed Him openly,
1 Corinthians 15:4
and that He was buried, and that He rose again the
third day according to the Scriptures,
Matthew 17:43
and they will kill Him, and the
third day He will be raised up.” And they were exceedingly sorrowful.
Matthew 20:19
and deliver Him to the Gentiles to mock and to scourge and to crucify. And the
third day He will rise again.”
Matthew 27:64
Therefore command that the tomb be made secure until the
third day, lest His disciples come by night and steal Him
away, and say to the people, ‘He has risen from the dead.’ So the last deception will be worse than the first.”
Mark 9:31
For He taught His disciples and said to them, “The Son of Man is being betrayed into the hands of men, and they will kill Him. And after He is killed, He will rise the
third day.”
I could go on and on and on, but I'll leave it there. He rose on the third day, meaning:
-First day: The day that the counting starts on
-Second day: One day after that
Third day: Two days after counting is started
[FONT=ARIAL,HELVETICA,SANS-SERIF]"A short time in the morning of the seventh day is counted as the seventh day; circumcision takes place on the eighth day, even though, of the first day only a few minutes after the birth of the child, these being counted as one day." Jewish Encyclopedia, Volume 4, page 475.
[/FONT]
This is a practice known as "inclusive reckoning." You can read more about it in the following links:
Three Days and Three Nights
Orthodox Judaism: Inclusive Reckoning, forty days and forty nights, david rosenblum
IOW, the expression "three days and three nights" is one that can fall into inclusive reckoning.