Resurrection of the dead in the Old Testament:
Elijah revived the son of the widow of Zarephath (which belongs to Sidon) (1 Kgs. 17: 22), and Elisha revived the son of the Shunammite woman (2Kgs. 4: 35)… The raising of those was a tribute to Christ's resurrection, a prophecy preceding and proclaiming the chances of the resurrection from among the dead … Also the story of Jonah the prophet and his burial for three days in the belly of the great fish was a symbol to Christ's burial and resurrection: "For 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." (Mt.12:40).
So all along the Old Testament, God wanted to make His people's minds ready to accept Christ the Lord's resurrection from among the dead … A tribute to our own resurrection … Now through baptism and in eternity indeed.