Until the episode at the tower of Babel (recorded in Genesis 11), everyone had a single language with a common speech. That desire for power and control which first showed itself at mans’ fall, became evident when some “would-be” leaders decided to make themselves appear as gods over all men by creating a great tower that reached up to the heavens where “only God can be.” To put down the rebellion, God severed their line of communications –removing their ability to control others by confusing the language and speech. The opportunity to have power over all humanity was lost when the people were divided into many smaller groups –each speaking their own language and going their own way.
Then they said, “Come, let us build ourselves a city, with a tower that reaches to the heavens, so that we may make a name for ourselves and not be scattered over the face of the whole earth.” But the LORD came down to see the city and the tower that the men were building. The LORD said, “If as one people speaking the same language they have begun to do this, then nothing they plan to do will be impossible for them. Come, let us go down and confuse their language so they will not understand each other.” So the LORD scattered them from there over all the earth, and they stopped building the city. That is why it was called Babel– because there the LORD confused the language of the whole world. From there the LORD scattered them over the face of the whole earth. (Genesis 11:4-9)
From that time on, nations have been unable to effectively communicate with each other because of the difference in their languages. However, at Pentecost God broke through the language barrier –supernaturally. He used the apostles and others, speaking in languages they didn’t know, to tell about His plan of redemption that had been completed through Jesus.