Resurrection on the Third Day

Question:
Why was Jesus raised from the dead after three days? Why not after 3 hours or even after 7 days (since 7 tends to denote fullness or perfection in the Bible)? What was happening in those three days that couldn't happen sooner – Jesus being God and all things being possible for Him – or is this a point of little significance that doesn't merit much dwelling on?
Answer:
The Bible does not directly address the question of why Jesus had to rise precisely on the third day and not before or after. However, the Scripture does give quite a bit of significance to this truth.
Paul wanting to remind the Corinthians of the gospel he had preached to them begins by talking about the importance of the gospel in their lives, and then proceeds to list out the important elements of the message. One of the central aspects of the message, which Paul delivered as of first importance, was that Christ "was raised on the third day in accordance with the Scriptures" (1 Corinthians 15:4, emphasis mine). Paul may have had in mind several portions of the Old Testament (cf. Ps. 16:10-11; Isa. 53:10b; Hos. 6:2) whose fulfillment he saw in the resurrection of Christ. But, while there are various passages that mention the fact of Christ's resurrection, it's hard to find one that says anyone would rise on the third day.
So what did Paul have in mind when he affirmed that Christ "was raised on the third day in accordance with the Scriptures"? He may have been referring to the prophetic words of the Lord Jesus Christ himself – "For just as Jonah was three days and three nights in the belly of the great fish, so will the Son of Man be three days and three nights in the heart of the earth" (Matthew 12:40). Suffice it to say, that Jesus rose again on the third day to fulfill His own prophetic words.
Coming to the next part of the question – what happened in the time between Jesus' death and resurrection? Again, we're simply not told. The passages that are usually quoted in this regard are Ephesians 4:8-9 and 1 Peter 3:18-20. However, I do not believe that these passages describe Jesus' activity between His death and resurrection.
The first one mentions the phrase "he had also descended into the lower regions, the earth" which is taken as Jesus' descent into Hades during the time between His death and resurrection. I think Paul simply was referring to the grave when he said that Jesus "also descended into the lower regions, the earth."
The second passage is an incredibly complex one. We need a correct understanding of the phrase "being put to death in the flesh but made alive in the spirit" to interpret the passage right. Peter is using the phrases "in the flesh" and "in the spirit" as exact parallels. The meaning then is that in His human sphere Christ was put to death, but in His resurrected sphere He went and made proclamation to the spirits in prison. I take the passage to mean that in His ascension the risen Christ made this proclamation. In summary, the Bible is not very clear about what Christ did between His death and resurrection.
Revanth T