Revelation 11:3-4

3 And I will grant the power of prophecy to My two witnesses for 1,260 (42 months; three and one-half years), dressed in sackcloth. 

Once again this is a sweet thing! John is shown our Father empowering His two witnesses for the same 3 ½ years. John sees the power and glory of Jesus flowing, even during these turbulent times. The message of the witnesses is great, yet these two are extremely humble with what they have been empowered by our Father to do. This is why we are shown that they are dressed in sackcloth. 

4 These [witnesses] are the two olive trees and the two lampstands which stand before the Lord of the earth.

The two olive trees are Zerubbabel and Joshua, Zechariah 4:14. These two men led the captives out of Babylon, Zechariah 4:7 and the two olive trees continuously provide oil, which is the Word of God through the power of the Holy Spirit, not by physical might, Zechariah 4:6.

These are literally two witnesses who will be used by our Father to deliver many people out of Babylon. We will see later in Revelation that Babylon is the worlds system of government and economics. So for 3 ½ years we will see the power of our Father flowing miraculously through these two witnesses. Didn’t Jesus preach for 3 ½ years as well? Some teach that these two witnesses are only symbolic and that they represent the Word of our Father. But we will study later that these two witnesses are killed and allowed to lay dead in the streets. Can the Word of our Father be killed by man? Can the Word of God lay dead or inactive? Absolutely not, the Word is alive, it is quick, and it is sharper than any two edged sword! So these two have to be real men and not a symbolic representation of the Word.  

5 And if anyone attempts to injure them, fire pours from their mouth and consumes their enemies; if anyone should attempt to harm them, thus he is doomed to be slain. [II Kings 1:10; Jer. 5:14.] 

Just like with Jesus, these two have a time to serve and a time to die. Our Father is in control and they do not die until their time is finished, or pre-planned by our Father. And just as with Jesus, they use the Word of God as their sword. This means that Grace will abound as well through them, just as it did with Jesus. Jesus healed those who hated Him. He fed those who would later call for His death. He forgave sinners and He even served the Gentiles, Who He was not called to serve. Our Father is Love and His love will always be shown, even during His wrath.