He had a trove of these oral accounts and written documents that he had gathered so he felt there was a need to put all of this information into one orderly account. After carefully sorting and investigating everything it seemed good to him to write it.  

He wrote it for a certain person, a “most excellent Theophilus.”  This name means “a lover of God.”  As mentioned earlier in our study, the title, “most excellent,” suggests this person likely held a high position in society,  and was no doubt well educated himself.  He evidently was a new convert who loved God deeply, but needed assurance or certainty about the things he had been taught.  Having a document that was thoroughly researched and well written, including Old Testament prophecy fulfilled in their lifetime and historical details to verify their authenticity, would provide a basis for confidence and certainty for growing a life of faith. 

Once the book became known and circulated it was received so well by the church that it was recognized as authentic and inspired by God, thus it was included in the New Testament canon. Read and study the Bible with confidence!