Hour

Boyd’s Bible Dictionary:

(time). First division of Jewish day, morning, noon, evening (Psa. 55:1717Evening, and morning, and at noon, will I pray, and cry aloud: and he shall hear my voice. (Psalm 55:17)). Night had three watches (Ex. 14:2424And it came to pass, that in the morning watch the Lord looked unto the host of the Egyptians through the pillar of fire and of the cloud, and troubled the host of the Egyptians, (Exodus 14:24); Judg. 7:1919So Gideon, and the hundred men that were with him, came unto the outside of the camp in the beginning of the middle watch; and they had but newly set the watch: and they blew the trumpets, and brake the pitchers that were in their hands. (Judges 7:19); Lam. 2:1919Arise, cry out in the night: in the beginning of the watches pour out thine heart like water before the face of the Lord: lift up thy hands toward him for the life of thy young children, that faint for hunger in the top of every street. (Lamentations 2:19)). Later, day was, morning, heat, midday, evening. Hours introduced from Babylon, after captivity (Matt. 20:1-101For the kingdom of heaven is like unto a man that is an householder, which went out early in the morning to hire laborers into his vineyard. 2And when he had agreed with the laborers for a penny a day, he sent them into his vineyard. 3And he went out about the third hour, and saw others standing idle in the marketplace, 4And said unto them; Go ye also into the vineyard, and whatsoever is right I will give you. And they went their way. 5Again he went out about the sixth and ninth hour, and did likewise. 6And about the eleventh hour he went out, and found others standing idle, and saith unto them, Why stand ye here all the day idle? 7They say unto him, Because no man hath hired us. He saith unto them, Go ye also into the vineyard; and whatsoever is right, that shall ye receive. 8So when even was come, the lord of the vineyard saith unto his steward, Call the laborers, and give them their hire, beginning from the last unto the first. 9And when they came that were hired about the eleventh hour, they received every man a penny. 10But when the first came, they supposed that they should have received more; and they likewise received every man a penny. (Matthew 20:1‑10)). An indefinite time (Dan. 3:66And whoso falleth not down and worshippeth shall the same hour be cast into the midst of a burning fiery furnace. (Daniel 3:6); Matt. 9:2222But Jesus turned him about, and when he saw her, he said, Daughter, be of good comfort; thy faith hath made thee whole. And the woman was made whole from that hour. (Matthew 9:22)).

Concise Bible Dictionary:

Used with various significations in scripture: as
1. An indefinite period, when the wordtime” gives the sense: “the hour cometh when ye shall neither in this mountain, nor yet at Jerusalem, worship the Father” (John 4:2121Jesus saith unto her, Woman, believe me, the hour cometh, when ye shall neither in this mountain, nor yet at Jerusalem, worship the Father. (John 4:21)).
2. A definite point of time, when “moment” or “at once” would give the sense. “The woman was made whole from that hour” (Matt. 9:2222But Jesus turned him about, and when he saw her, he said, Daughter, be of good comfort; thy faith hath made thee whole. And the woman was made whole from that hour. (Matthew 9:22)).
3. The division of the day into twelve hours, generally considered to be from sunrise to sunset. This varied in Palestine, from ten of our hours in the winter to fourteen in the summer; so that the hours in summer would be nearly half as long again as in the winter. The hours of scripture are now usually reckoned from 6 o’clock A.M. to 6 o’clock P.M., which would make the third hour our 9 o’clock; the sixth hour our 12 o’clock; the ninth hour our 3 o’clock P.M., and so on.
This would be applicable to all the definite hours mentioned in the New Testament except in the Gospel by John. This evangelist followed the plan of reckoning from midnight to midnight. This explains the difficulty found in John 19:1414And it was the preparation of the passover, and about the sixth hour: and he saith unto the Jews, Behold your King! (John 19:14), which represents the trial proceeding at the sixth hour, whereas Mark 15:2525And it was the third hour, and they crucified him. (Mark 15:25) says “It was the third hour and they crucified him.” A comparison of all the passages shows that the trial commenced early, and our 6 o’clock suits very well; and the crucifixion at 9 o’clock, the third hour of the Jews, agrees with Mark. The other definite times mentioned in John are in John 1:3939He saith unto them, Come and see. They came and saw where he dwelt, and abode with him that day: for it was about the tenth hour. (John 1:39); John 4:6, 52-536Now Jacob's well was there. Jesus therefore, being wearied with his journey, sat thus on the well: and it was about the sixth hour. (John 4:6)
52Then inquired he of them the hour when he began to amend. And they said unto him, Yesterday at the seventh hour the fever left him. 53So the father knew that it was at the same hour, in the which Jesus said unto him, Thy son liveth: and himself believed, and his whole house. (John 4:52‑53)
, and the now common method of reckoning the time will agree with all of them.

From Manners and Customs of the Bible:

The Jewish day was reckoned from evening to evening. See note on 1 Corinthians 15:44And that he was buried, and that he rose again the third day according to the scriptures: (1 Corinthians 15:4) (#868). The word “day” was, however, used in another sense also, as with us, to denote that portion of the twenty-four hours during which the sun shone. While the night was divided into watches (see note on Mark 13:3535Watch ye therefore: for ye know not when the master of the house cometh, at even, or at midnight, or at the cockcrowing, or in the morning: (Mark 13:35), #743) the day was divided into hours; each of these hours being one twelfth of the time between sunrise and sunset Thus the hours varied in length according to the time of year, the summer hours being longer than those of winter. In the latitude of Palestine the longest day has, according to our reckoning, fourteen hours and twelve minutes, and the shortest nine hours and forty-eight minutes. This makes a difference of four hours and twenty-four minutes between the longest day and shortest. If we divide the day into twelve hours, there will be found a difference of twenty-two minutes between the longest hour and the shortest, the length of the hour varying from forty-nine minutes to seventy-one.
The first hour began at sunrise, the sixth ended at noon, and the twelfth ended at sunset. The third hour divided the period between sunrise and noon, and the ninth between noon and sunset. The first at its close corresponded nearly to seven o’clock A. M. of our time, and the twelfth hour to six o’clock P. M.
The “third hour” is mentioned in Matthew 20:33And he went out about the third hour, and saw others standing idle in the marketplace, (Matthew 20:3); Mark 15:2525And it was the third hour, and they crucified him. (Mark 15:25); Acts 2:1515For these are not drunken, as ye suppose, seeing it is but the third hour of the day. (Acts 2:15). It may, be roughly reckoned at nine o’clock A. M. of our time. The “sixth hour” is named in Matthew 20:5; 22:455Again he went out about the sixth and ninth hour, and did likewise. (Matthew 20:5)
45If David then call him Lord, how is he his son? (Matthew 22:45)
; Mark 15:3333And when the sixth hour was come, there was darkness over the whole land until the ninth hour. (Mark 15:33); Luke 23: 44; John 4:6; 19:146Now Jacob's well was there. Jesus therefore, being wearied with his journey, sat thus on the well: and it was about the sixth hour. (John 4:6)
14And it was the preparation of the passover, and about the sixth hour: and he saith unto the Jews, Behold your King! (John 19:14)
; Acts 10:99On the morrow, as they went on their journey, and drew nigh unto the city, Peter went up upon the housetop to pray about the sixth hour: (Acts 10:9). It corresponded exactly to twelve o’clock noon of our time. The “seventh hour” is mentioned in John 4:5252Then inquired he of them the hour when he began to amend. And they said unto him, Yesterday at the seventh hour the fever left him. (John 4:52). It was about one o’clock P. M. The “ninth hour” is spoken of in Matthew 20:5; 27:45-465Again he went out about the sixth and ninth hour, and did likewise. (Matthew 20:5)
45Now from the sixth hour there was darkness over all the land unto the ninth hour. 46And about the ninth hour Jesus cried with a loud voice, saying, Eli, Eli, lama sabachthani? that is to say, My God, my God, why hast thou forsaken me? (Matthew 27:45‑46)
; Mark 15:33, 3433And when the sixth hour was come, there was darkness over the whole land until the ninth hour. 34And at the ninth hour Jesus cried with a loud voice, saying, Eloi, Eloi, lama sabachthani? which is, being interpreted, My God, my God, why hast thou forsaken me? (Mark 15:33‑34); Luke 23:4444And it was about the sixth hour, and there was a darkness over all the earth until the ninth hour. (Luke 23:44); Acts 3:1; 10:31Now Peter and John went up together into the temple at the hour of prayer, being the ninth hour. (Acts 3:1)
3He saw in a vision evidently about the ninth hour of the day an angel of God coming in to him, and saying unto him, Cornelius. (Acts 10:3)
. It was about three o’clock P. M. The tenth hour” is named in John 1:3939He saith unto them, Come and see. They came and saw where he dwelt, and abode with him that day: for it was about the tenth hour. (John 1:39). It was about four o’clock P. M. Some commentators, however, contend that John, writing this Gospel in the later years of his life, referred to Roman time and not to Jewish, thus making the hour ten o’clock A. M. This could hardly be, unless all his other estimates of time were reckoned in the same way, which, from a consideration of various texts, is highly improbable; besides, as Lucke (cited by Alford) remarks, even among the Romans the division of the day into twelve equal hours was, though not the civil, the popular way of computing time. The “eleventh hour” is mentioned in Matthew 20:6,96And about the eleventh hour he went out, and found others standing idle, and saith unto them, Why stand ye here all the day idle? (Matthew 20:6)
9And when they came that were hired about the eleventh hour, they received every man a penny. (Matthew 20:9)
, and corresponds nearly to five o’clock P. M.