Forty and two months is 1260 days. This once again implies that each month is 30 days, and a year is 360 days. God is always the same.
MALACHI 3:6 For I am the LORD, I change not.
( We don’t know who these prophets are yet but we can know more about: see James 5:17. “Elias (Elijah) was a man subject to like passions as we are, and he prayed earnestly that it might not rain: and it rained not on the earth by the space of three years and six months.”
3½ years is the same as 42 months, is the same as 1260 days.)
Scriptural basis
The fact is that we cannot use a Gentile calendar. In Isaiah we read that everything has to be according to the law and the testimony (which are the Words of God).
Isaiah 8:19 And when they shall say unto you, seek unto them that have familiar spirits, and unto wizards that peep, and that mutter: should not a people seek unto their God? for the living to the dead?
20 To the law and to the testimony: if they speak not according to this word, it is because there is no light in them.
We have to be very careful, are therefore living very dangerously if we try use anything that is not Scriptural or biblical, to explain the Scriptures. We cannot compromised with the world, when it comes to God’s words.
Our modern day calendar
There are many reasons that we cannot use Gentile years for Biblical prophecies. Julius Caesar only got the Gentile calendar correctly lined up in “the year of confusion” (45 BC), when he added 90 days to realign the calendar with the earth’s seasons. After that Augustus Caesar also made a change involving a few days in the calendar
Pope Gregory 13th finalized the current calendar in AD 1582. He did this by adjusting the leap years at the beginning of each century. Ten days were removed from the month and October 4 was followed by October 15. All these changes make it almost impossible for anybody to determine exactly (i.e., to the day) any of the dates used in some prophecies. We can however safely and accurately work with the nearest part of a year.
