Hi Donna ,

To correctly understand Revelation 11:1-2 you must first read the immediately previous Scripture , ie. Revelation 10:11  which sets the context for understanding  Revelation 11:1-2. 

Revelation 10:11

"And he said un to me , Thou must PROPHESY AGAIN BEFORE many PEOPLE,  and N ATIONS,  and TONGUES , and kings."  ( John is directed to PROPHESY AGAIN about Rev 7:9 )

John PROPHEIED  BEFORE  in Revelation  7:9  of many people, and  nations, and tongues in :

 Revelation  7:9

"After this I beheld a GREAT MULTITUDE , which no man could number,  of ALL NATIONS , and kindreds , and PEOPLE,  and TONGUES stood before the throne and before the Lamb"

SO THERE YOU HAVE IT:

 John was directed to PROPHESY AGAIN ( Rev 10:11 ) about the GREAT MULTITUDE OF GENTILES IN HEAVEN ( Rev 7:9 ) , not some group of Gentiles on earth. Therefore, in  Revelation 11:1-2  John is directed to "measure the temple of God" in heaven , not on earth. The outer court of the temple of God in heaven is "given unto the Gentiles" , ie. the raptured great multitude which is the Gentile Body of Christ Church in heaven  spoken of in Rev 7:9 , "and the Holy City ( in heaven ) shall they tread underfoot for forty-two months".   

These Scriptures reveal to us that the great multitude of Gentiles in heaven , which is the raptured Gentile Body of Christ Church,  will  be in heaven for the exact same forty-two months that Satan's anti-Christ, AFTER receiving his power, will "continue" for forty-two months on earth ( Rev 13:5 ). The Gog-Magog War in Israel immediately precedes the resurrection /rapture of the Church.

Blessings to you,