Luke 1:4 “that you may know the certainty of those things in which you were instructed.”
Since we do not know the age of Theophilus, is possible that he was instructed while young. In any case, it seems that, like Luke, he did not have any first-hand experience of the events of the Gospel.
It is important for us to pick up on something here. Luke acts as if the truth is something to be considered, and then accepted. It needs to be studied. A sort of mental assent is required. A person is not just simply expected to accept it whole cloth, but to consider it and accept after thinking it over. So, as we have already seen, faith is needed. But that faith is not based on an unfounded belief, but on a reasonable conclusion.
Heavenly Father, thank You for the facts of the gospel. And thank You for the faith that You have given us in Your word. You lead us to a place of trust. You help us to see that Your Word is dependable. Give us a reliance on it that is unshakeable. As your Word, is worthy of honor. We will obey it for all of our lives. In the name of the Lord Jesus Christ I pray and praise You, Amen.