They devoted themselves to the apostles' teaching and fellowship, to the breaking of bread and to prayer.

Act 2:42 "They" meaning the three thousand people whose lives were changed at Pentecost , because they devoted their lives to Jesus Christ. 

Primarily, they studied God's Word, which was the "apostles' teaching." Their teaching and letters consisted of stories of Jesus' love, His miracles, and simple the things that made Him to be our Savior. The closer the three thousand people got to knowing Jesus, the closer the three thousand became of one mind creating the body of Christ. 

Secondly, they began to fellowship with each other, which incorporates a whole list of things from simply talking to each other, up to supporting one other in time of need. Fellowship includes much more than just say a quick hello and the typical sunday morning social questions. Fellowship is what we will be spending much of eternity doing, its about developing eternal relationships with your brothers and sisters in Christ. 

Thirdly, the people became to "break bread" or eat together. Image a world without Costco; you cant buy salmon by the fillet, you cant buy chicken by the pound, and you can not buy fruits and vegetables in the quality or quantity we can today. People worked hard for the food they had. I have been doing a lot of fishing this past year and regardless of the type of fish, it takes time in order to catch fish. One day i was trolling for salmon with my buddy Rob for close to 9 hours before we got a bite, and we only took home one fish. Now keep that thought in mind and thing about this: you spent your whole day fishing for that fish and it might feed your family if your lucky, now do you think you would want guest over as well? absolutely not, because in their culture the pot luck did not exist, if you asked someone to come over to eat its because you had food to share with them. Logically thinking, for the common man there is no way you could be sure you would catch fish for the next night. They became of one mind and for that they set their eyes on whats eternal. They broke bread with their eternal family members, and didn't allow the worries of this life to effect their fellowship. Where God abides, God provides. 

Lastly, they spent time in prayer together. There is power in prayer, when we take time to talk to God, he is listening. Jesus tells us in Matthew 18:20 "For where two or three come together in my name, there am I with them." I need to spend more time with my brothers and sisters in prayer. I all too often find myself praying alone, and there is nothing wrong with that. But the power that I can harness in a group setting, can move a mountain. In today's culture, I want to be used to move those mountains. A revival is coming.