Passage
The former treatise I made, O Theophilus, of all things which Jesus began to do and to teach,
The former treatise I made, O Theophilus, of all things which Jesus began to do and to teach,
Acts 1:1 The former treatise I made, O Theophilus, of all things which Jesus began to do and to teach,
Acts 1:2 Until the day on which, giving commandments by the Holy Ghost to the apostles whom he had chosen, he was taken up.
Acts 1:3 To whom also he shewed himself alive after his passion, by many proofs, for forty days appearing to them, and speaking of the kingdom of God.
The verse centers on "all things", "former", "treatise", "theophilus", "jesus", "began", and "teach". It is saying that the verse draws attention to "all things" and "former", so its meaning should be read from those terms before moving to application.
The next verse adds "Until the day on which giving commandments...", so "all things" and "former" should be read forward into that movement. In Acts context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "all things" and "former" with trust shaped by these words, not by a vague optimism outside the passage.