It happens when you are walking with God intimately. Everything about the bible is so real and very living, as if the bible has its own life, every minutes is revelations while reading. But if you don't serve God fully, you hardly pray, you no longer praise Him, no giving thanks, you no longer talked about the joy of your salvation, this time, reading the bible is so boring.
To maintain our christian life on fire, you should spend much time in prayer at least 2 or more hours a day. 10 or 30 minutes is not enough. Pray without ceasing is the key. have you experienced that even in dreams you were praying? if so, you are the one being talked about of this verse- 1 Thessalonians 5:17.