The 3rd seal is the third part of a prophecy of the 7 seals found in Revelation 6,8. I believe the 3rd Seal is predicting the final and most important worldwide mission of God's remnant people in our time starting with the outpouring of the Holy Spirit (latter rain) required for their ministry during a time of spiritual famine and darkness in the world (which is fast approaching).
When we let the bible interpret itself the symbols used in prophecy unlock the mystery of the interpretation and allow us to determine the fulfillment events. The meaning of the symbols are in the bible itself, lets examine:
3rd Seal
When He opened the third seal, I heard the third living creature say, "Come and see." So I looked, and behold, a black horse, and he who sat on it had a pair of scales in his hand. And I heard a voice in the midst of the four living creatures saying, "A quart of wheat for a denarious, and three quarts of barley for a denarius; and do not harm the oil and the wine."
The horse and riders are personifications to help portray the surrounding symbols. The word black can simply mean literal or spiritual blackness or darkness. The word black in the bible can also represent famine and lack of water, where faces are turned to blackness because of lack. An example of this is in Lamentations, and Jeremiah:
Our skin was black like an oven because of the terrible famine.
and
Judah mourneth, and the gates thereof languish; they are black unto the ground; and the cry of Jerusalem is gone up.... they came to the pits, and found no water; ...Because the ground is chapt, for there was no rain in the earth,
The famine described by the black horse can be interpreted as a literal famine like lack of bread and water, however in light of all the other symbols in the 3rd seal (See Oil, Wine) it more likely relates to a spiritual famine similar to the one described in Amos 8:11-14. In the bible bread represents Jesus and the word of God (John 6:33, Matthew 4:4) and water represents the gospel (John 7:37,38, John 4:14). The famine being described therefore is a time of dense spiritual darkness and godlesness where the true light of the gospel has been almost extinguished and the truth about Jesus as God is hard to come by and rare among all the falsehood.
The scales are an instrument used to measure. Measuring in the bible represents God measuring and evaluating his people or the state of the inhabitants of the world. This is the same metaphor used by God to pronounce judgement on Belshazzar king of Babylon before Babylon was overthrown by the Medes and Persians:
...Thou art weighed in the balances, and art found wanting.
Likewise, Job uses the same metaphor to contend with God about the justice of his infirmity.
Let me be weighed in an even balance, that God may know mine integrity.
The scales are also associated with the beginning of the ministry of the two witnesses, which I believe is a parallel prophecy expanding on the the 3rd Seal. Here also an angel is instructed to measure the temple and worshipers which are the people who claim to be his followers, in other words Christians.
And there was given me a reed like unto a rod: and the angel stood, saying, Rise, and measure the temple of God, and the altar, and them that worship therein.
The scales therefore represent a period of time when God is going to look down and evaluate the state of all those who are his followers and are called by his name and determine who of them is actually following his instructions and living by his standards and on the other hand who of them is living in dense darkness and self imposed spiritual starvation.
Wheat and barley are grains used to make bread. Bread in the bible represents Jesus and the word of God (John 6:33, Matthew 4:4). In the description above a quart of wheat is said to cost a denarious and three quartz of barely for a denarious. In those days days a denarious was a days wage for an agricultural worker (Matt 20:2).
Therefore what these symbols are telling us is that there will come a time that it will cost you a whole days work to earn enough to buy bread just to feed yourself, or barley just to feed your family. This could off course be referring to literal scarcity and high cost of food which is already a reality for the majority of our third world, however more then likely and in line with the other symbols, this is referring to spiritual cost of following Jesus. In other words a time is coming when it will cost you significant personal time or worldly sacrifice just to find, learn and practise the word of God as revealed in the bible. Establishing a firm living connection with Jesus at that time will come at a great personal cost for those who have not done so already and prepared before hand.
It is also important to note that wheat and barely are both crops heavily dependent on rain, and the latter rain in particular is a symbol of the final outpouring of the Holy Spirit. Therefore we can see here a time where one group of people does not receive the latter rain and as a result there is a general scarcity of bread which are the true words and acts of Jesus.
Oil is well known symbol of the Holy Spirit, it goes all the way back to the tabernacle that God gave instructions for Moses to build where olive oil was used as fuel for the lamps inside the Holy Place (Exodus 27:20). A scented olive oil was also used by the Israelites to be a holy anointing oil for prophets and kings. By the Christian era it was well understood that the anointing oil represented the outpouring of the Holy Spirit:
You know of Jesus of Nazareth, how God anointed Him with the Holy Spirit and with power, and how He went about doing good and healing all who were oppressed by the devil, for God was with Him.
The wine is also a symbol of the outpouring of the Holy Spirit. Wine has an effect on people when they drink it, it makes them happy, it makes them more open and bold in their behaviour and relationships. This is a similar effect of the outpouring of the Holy Spirit, people are emboldened to preach the gospel and they have a heightened sense of empathy for the salvation of their fellow men.
When the Holy Spirit was poured out at pentecost, people also thought the disciples were drunk with wine:
And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance. ... Others mocking said, These men are full of new wine. But Peter, standing up with the eleven, lifted up his voice, and said unto them... For these are not drunken, as ye suppose, seeing it is but the third hour of the day. But this is that which was spoken by the prophet Joel; And it shall come to pass in the last days, saith God, I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams.
Furthermore the prophet Zechariah also clearly foretold of the same outpouring of the Holy Spirit on the faithful remnant before the great day of the Lord:
The Lord will be seen over them, And His arrow will go forth like lightning. The Lord God will blow the trumpet ...
The LORD of hosts shall defend them; and they shall devour, and subdue with sling stones; and they shall drink, and make a noise as through wine; and they shall be filled like bowls, and as the corners of the altar.
Ask the Lord for rain in the time of the latter rain. The Lord will make flashing clouds; He will give them showers of rain,...
And they of Ephraim shall be like a mighty man, and their heart shall rejoice as through wine: yea, their children shall see it, and be glad; their heart shall rejoice in the LORD.
Here we see wine again used as a metaphor to describe the state of those mighty men who will powerfully proclaim the gospel message. They are a parallel of the two witnesses from Revelation 11 and the Lord himself will be seen over them because they are His witnesses and he will lead the movement and supply the power for their witness in the form of the full outpouring of the Holy Spirit.
It would be unlikely that in a literal famine there would be a selective scarcity of resources as seen here. The fact that oil and wine are unusually plentiful during this famine leads us to seek a spiritual understanding of the symbols.
Since the oil and the wine represent the outpouring of the holy spirit or latter rain on the remnant people of God who are to close the work of the gospel, then the specific mandate not to harm them represents the divine protection assured to this movement and message for the duration of their ministry. While I believe there may be people who are persecuted and potentially killed during this period I believe there will be an evident divine protection on the movement as a whole in the way their message spreads to all nations worldwide despite severe opposition.
Secondly, this also represents a promise that the power of anointing through the Holy Spirit on those who follow Jesus will remain plentiful, and will be poured out in fullness without sparing.
The specific mandate not to harm the oil and the wine is also linked to the ministry of the two witnesses:
Two Witnesses
And I will give power to my two witnesses, and they will prophesy one thousand two hundred and sixty days, clothed in sackcloth. These are the two olive trees and the two lampstands standing before the God of the earth.
And if anyone wants to harm them, fire proceeds from their mouth and devours their enemies. And if anyone wants to harm them, he must be killed in this manner.
This link helps us interpret the 3rd seal because it creates a direct parallel between it and the ministry of the two witnesses: A divinely protected group of people who powerfully proclaim the warnings of prophecy and coming plagues while in deep repentance and sorrow over imminent judgement. The mandate not to harm the oil is associated with the mandate not to harm the olive trees which are the source of the oil.
The 3rd Seal represents the final and most important mission of God's remnant people in our time starting with the outpouring of the Holy Spirit (latter rain) required for their ministry during a time of spiritual famine and darkness in the world (fast approaching). It will be a time of powerful witnessing and warning the world of imminent destruction followed by the second coming of Jesus to save those who call on his name for deliverance. It will be like the day of pentecost when the disciples of Jesus received the holy spirit to begin the gospel ministry of the Christian era, however the closing work of the gospel will be done with greater power, signs and wonders then the opening.