You want to know what came of the devotion of the apostles? Hundreds of people were affected by generosity. They worshipped together daily in the temple, they gave away their possesions, they shared their meals, they gave to the poor, and they shared the good will of all the people. These guys were popular, and the Word says that their numbers were added to daily. Every day people were being saved! You want to know what that looks like? Try this, in Acts 2:14-41 Peter speaks to a multitude after being filled with the holy spirit (that's right, after being with 120 people who were devoted to praying) 3,000 people were saved in one day alone. 3,000 people! And every day people were being saved.They all met together and were constantly united in prayer. -Acts 1:14A
All the believers devoted themselves to the apostles' teaching, and to fellowship, and to sharing in meals (including the Lord's Supper), and to prayer. -Acts 2:42
This is a picture of the church. A little different from what we have today, isn't it! But do you see what can happen through devotion?
God is devoted to us, and he wants to use people who are devoted to him, in even so much as being devoted to your fellow man; sharing meals, selling your posessions and giving to the poor, worshipping together, and ultimately, devotion to a personal relationship with God.
So where do you start with devotion to God? From an Adventist Youth's point of view, this is a good question since Adventism seams to teach everything but having a personal relationship with God. In any relationship the best place to begin is with communication; getting to know the other--relating. Talk to God like you would anyone you were face to face with, talk to him as often as you think of it, and set aside time (in the morning before you start your day is good) to talk with him. Read the Word; get a study Bible in an easy translation (I prefer New Living Translation). Hang out with your Christian peers, ask questions and discuss; as you relate with them they will help you grow stronger.
These are just a few ideas, your personal relationship with God will be unique to you.
Remember that devotion isn't work or something you 'have to do', devotion should be a pleasure. Acts 2:46 tells us the believers didn't just do all these things, they did them with great joy and generosity, verse 47 even says they praised God the whole time, and even enjoyed the good will of all the people.
And finally remember that because God has devoted himself to us in so much as to die an excruciating death for us, he is most worthy of our devotion, our praise and our worship.