A miracle is defined as follows: An effect or extraordinary event in the physical world that surpasses all known human or natural powers and is ascribed to a supernatural cause; an effect or event manifesting or considered as a work of God (Dictionary.com). There are many miracles scattered throughout the Old Testament introducing mankind to the wonderous powers of a great Creator that goes by many names, ie: God, Allah, Elohim. While scientists can explain many miraculous occurrences with methodical measures, there are other phenomenon they cannot disavow in analytical terms.
Miracles Recorded in the Old Testament
1. Creation. Creation of the universe, including plants, animals and humans. (Gen. 1-2).
2. Enoch's Translation - Enoch was taken out of the world without dying. (Gen. 5:24)
3. Worldwide Flood. The great flood of Noah. (Gen. 7, Gen. 8)
4. Confusion of Tongues. Confusion of languages at Babel. (Gen. 11:1-9).
5. Sodom and Gomorrah Destroyed. Destruction of Sodom and Gomorrah. (Gen. 19:4).
6. Pillar of Salt. Lot’s wife turned into a “pillar of salt”. (Gen. 19:26)
7. Closing of the Wombs of Abimelech's Household - Women of Abimelech's house became barren and was not able to have children. (Gen. 20:17,18)
8. Birth of Isaac. Sarah and Abraham conceive a child in their old age. (Gen. 21:1).
9. Burning Bush not Consumed. Moses before the burning bush that did not burn the bush. (Ex. 3:3).
10. Miracle of Aaron’s Rod. Aaron’s rod changed into a serpent. (Ex. 7:10-12).
11. The Plagues of Egypt. The ten plagues imposed upon Egypt. (Ex. 7:20/Ex. 12:30).
12. Pillar of Cloud and Fire – A cloud by day and a fire by night led the Israelites through the desert. (Ex. 13:21–22; 14:19–20)
13. Miracle of the Red Sea Parting. Red Sea divided; Israel passes through on dry ground. (Ex. 14:21).
14. Waters of Marah Sweetened. God answers Moses prayer for water in the wilderness. (Ex. 15:23-25).
15. Manna From Heaven. Manna (food) sent daily, except on Sabbath. (Ex. 16:14-35)
16. Water from the Rock at Rephidim. Moses smites the rock and water came out. (Ex. 17:5).
17. Fire Devours Nadab and Abihu. Nadab and Abihu consumed [by fire] for offering “strange fire”. (Lev. 10:1, 2).
18. Fire From the Lord Burns the People. Some of the people consumed by fire at Taberah. (Num. 11:1-3).
19. Earth Swallows Up Korah and Company. The earth opens and swallows up Korah and his army. (Num. 1:32).
20. Fire From the Lord Consumes Two Hundred and Fifty. Fire at Kadesh. (Num. 16:35-45).
21. 14,700 Slain By a Plague. People slain by plague at Kadesh for murmuring against Moses. (Num. 16:46-50).
22. Miracle of Aaron’s Rod. Aaron’s rod budding at Kadesh. (Num. 17:8).
23. Water From the Rock. Water from the rock, smitten twice by Moses, desert of Zin. (Num. 20:7-11).
24. The Miracle of the Brazen Serpent. The brazen serpent heals the people bitten by the fiery serpents. (Num. 21:8-9)
25. Balaam’s Donkey. Balaam’s [ass] speaks. (Num. 22:21-35).
26. Jordan River Parts. The Jordan divided, so that Israel passed over dryshod near the city of Adam. (Jos.3:14).
27. Jericho’s Walls Destroyed. The walls of Jericho fall down. (Jos. 6:6-20).
28. The Lord Stills the Sun and Moon. The sun and moon stayed to allow the Israelites to avenge their enemies. (Jos. 10:12-14).
29. The Lord Casts Stones From Heaven. A hailstorm destroys the enemy of the Israelites. (Jos. 10:12-14).
30. Dew on Gideon’s Fleece – God proves to Gideon he needs his assistance by allowing the dew to fall only on Gideon's fleece. (Jud. 6:37–40)
31. Strength of Samson. The Spirit of the Lord gives Samson supernatural strength. (Jud. 14-16).
32. Water From a Hollow Place of a Donkey’s Jaw. The Lord provides Samson water from a donkey’s jaw. (Jud. 15:19).
33. Dagon Idol Falls Before the Ark. Dagon falls twice before the ark. (1 Sam. 5:1-12).
34. Emerods (tumors) Befall the Philistines. Emerods on the Philistines. (1 Sam. 5:1-12)
35. 50,070 Men of Beth-shemesh Killed by the Lord. Men of Beth-shemesh smitten for looking into the ark. (1 Sam. 6:19).
36. The Lord Thunders a Great Thunder. Thunderstorm causes a panic among the Philistines at Eben-ezer. (1 Sam. 7:10-12).
37. The Lord Creates a Sound in the Mulberry Trees as a Sign to Attack the Philistines. Sound in the mulberry trees at Rephaim. (2 Sam. 5:23-25)
38. The Lord Kills Uzzah for Touching the Ark. Uzzah smitten for touching the ark at Perez-uzzah. (2 Sam. 6:6, 7).
39. King Jeroboam’s Hand Withers. King Jeroboam’s hand withered to get him to repent. (1 Kings 13:4)
40. King Jeroboam’s Alter Destroyed. Jeroboam’s new altar destroyed at Bethel. (1 Kings 13:4-6).
41. Miracle of Elijah and the Widow’s Oil Increase. Widow of Zarephath’s meal and oil increased. (1 Kings 17:14-16).
42. Miracle of Elijah and the Widow’s Son Raised From the Dead. Widow’s son raised from the dead. (1 Kings 17:17-24).
43. Miracle of the Drought. Drought incorporated by Elijah’s prayers. (1 Kings 17, 1st Kings 18).
44. Miracle of Fire. Fire incorporated by Elijah’s prayers. (1 Kings 18:19-39).
45. Miracle of Rain. Rain incorporated by Elijah’s prayers. (1 Kings 18:41-45).
46. Elijah Fed by Ravens. Elijah fed by ravens at the Kerith Ravine. (1 Kings 17:6).
47. Ahaziah’s Captains Consumed by Fire. Ahaziah’s captains consumed by fire near Samaria. (2 Kings 1:10-12).
48. Jordan River Divided. Jordan divided by Elijah and Elisha near Jericho (2 Kings 2:7, 8, 14).
49. Elijah Carried to Heaven. Elijah carried up into heaven without dying. (2 Kings 2:11).
50. Elisha Purifies the Waters of Jericho. Waters of Jericho healed by Elisha’s casting salt into them. (2 Kings 2:21, 22).
51. Elisha’s Curse Cause Bears to Kill 42. Bears out of the wood destroy forty-two “young men” at Bethel. (2 Kings 2:24).
52. The Lord Provides Water to Jehoshaphat and the Allied Army. Water provided for Jehoshaphat and the allied army (2 Kings 3:16-20).
53. Elisha and the Widow’s Oil Increase. The widow’s oil multiplied. (2 Kings 4:2-7).
54. Elisha and the Shunammite’s Son Raised From Dead. The Shunammite’s son given, and raised from the dead at Shunem. (2 Kings 4:32-37).
55. Elisha Cures the Deadly Pottage. The deadly pottage cured with meal at Gilgal. (2 Kings 4:38-41).
56. Feeding of the 100 Men. A hundred men fed with twenty loaves at Gilgal. (2 Kings 4:42-44).
57. Naaman Cured of Leprosy. Naaman cured of leprosy, Gehazi afflicted with it. (2 Kings 5:10).
58. Iron Axe Swims the River. The iron axe-head made to swim on the river Jordan. (2 Kings 6:5-7).
59. Elisha Knows the King of Syria’s Plans. Ben hadad’s plans discovered. Hazael’s thoughts, etc. (2 Kings 6:12).
60. The Syrian Army Blinded. The Syrian army smitten with blindness at Dothan. (2 Kings 6:18).
61. The Syrian Army Cured of Blindness. The Syrian army cured of blindness at Samaria. (2 Kings 6:20).
62. The Dead Revived. Elisha’s bones revive a dead man. (2 Kings 13:21).
63. God Sends Lions Into Samaria. God sends lions into Samaria because they did not fear the Lord. (2 Kings 17:25).
64. The Army Destroyed. Sennacherib’s army destroyed at Jerusalem. (2 Kings 19:35).
65. The Sun Goes Backward. Shadow of sun goes back ten degrees on the sun-dial of Ahaz in Jerusalem. (2 Kings 20:9-11).
66. Uzziah Struck With Leprosy. Uzziah struck with leprosy in Jerusalem. (2 Chronicles 26:16-21).
67. Three Hebrew Boys Delivered from the Fiery Furnace. Shadrach, Meshach, and Abed-nego delivered from the fiery furnace in Babylon. (Dan. 3:10-27).
68. Writing on the Wall. Daniel interprets the message supernaturally sent by God to Belshazzar. (Dan. 5)
69. Daniel in the Lion’s Den. Daniel saved in the lions’ den. (Dan. 6:16-23).
70. Jonah in the Belly of the Whale. Jonah in the fish’s belly for 3 days. (Jonah 2:1-10).
It is interesting to note there are 70 miracles recorded. The number 70 is mentioned many times throughout the Old Testament and considered to be a Holy number.
Reference: Christiananswers.net, Access-Jesus.com, Wikipedia.com