Believe in the teaching of the Lord Jesus Christ, not in the miracles.
Miracles happen every day. God is always at work, and even now, Jesus is working. One miracle is that God revives dead hearts and makes new creations out of unbelievers. Another is the miracle of the very earth upon which we stand. (Romans 1:20, Jeremiah 51:15, Job 12:7). Healings by God also occur, as families affected by them can attest.
The pro-consul was astounded. Acts 13:12 says. In the New Testament days immediately after Jesus’ resurrection and ascension, the Apostles were given power to perform miracles. One of these was the miracle that occurred by Paul in front of the pro-consul Sergius Paulus, a man of intelligence, so says Acts 13:7. Paul confronted a false prophet, a magician called bar-Jesus, and pronounced him false and then the power of God descended and caused the false prophet to go blind on the spot. The Pro-consul saw this happen.
Then the proconsul believed, when he saw what had occurred, for he was astonished at the teaching of the Lord. [underline mine]
Did the pro-consul believe in the miracle? NO. He believed the teaching of Jesus Christ. He understood the miracle was authentic, but it was the teaching in which he was moved.
The MacArthur Commentary says,
The missionaries’ victory was not only negative, as seen by the defeat of bar-Jesus, but also positive. Satan’s emissary had been defeated and silenced, and now Paul and Barnabas were about to win the battle for Sergius Paulus’ soul: … as so often is related in Acts, God used a miracle to confirm the authenticity of His messengers, and the truth of His word. Significantly, it was the teaching of the Lord, not the miracle he had just witnessed, that prompted the proconsul to believe. He was amazed at the teaching of the Lord, not at the miracle.
Remember, doctrine matters.
Why Doctrine Matters by Albert Mohler
Doctrine is, quite literally, the teaching of the church–what the church understands to be the substance of its faith. It is no substitute for personal experience
Why Doctrine Matters, by Ligonier
Doctrine is Biblical. Our English word doctrine is derived from a Latin word, doctrina, which means, “that which is taught.” In Christian usage, it refers to Christian teaching about Scripture, God, man, Christ, salvation, church, and the end of all things.
Doctrine Matters: Eternal Life Depends on It, by Kevon DeYoung
If you are interested in abiding with Jesus and abiding with the Father, you will care about the truth abiding in you. We will not know God unless we know the truth. Which is another way of saying: You do not get to heaven without theology. The promise of 1 John is that if the truth abides in you, you abide in God and you will receive what is promised to you: namely, eternal life.