Some claim that C2:15 is about a conspiracy to do with the great fire of London in 1666. However, I do not see how it can be because there was a King on the throne at the time and not a Queen.  Hence, why it is imperative that people look for the keys in the prophecies. Many of the prophecies of Nostradamus were also based upon biblical prophecies, so if you understand biblical prophecy you should be able to understand the prophecies of Nostradamus.
1. The fault is committed in London.
2. It relates to a 'sect' with a woman at the top of it.
3. Ancient lady falls from her high place, people connected to her killed.
4. Burnt through lightening
5. Number 66 = 6+6 = 12 and 12 is the number of the 'victim'.
In my humble view this prophecy relates to Jezebel (USA) mentioned in Rev 2. Jezebel that ran a sect called 'Summit Lighthouse' and Church Universal Triumphant in the USA. 1966 was the beginning of the expansion of it and it came out of Theosophy and HBB.
The biblical prophecies predicted that the children of Jezebel would be struck (spiritually) dead. Her name was Elizabeth Claire Prophet. Hence, she was the one that called herself a prophet as indicated by Rev 2. The bible also tells you that she refused to be a widow. In other words, she refused to go it alone and stand in integrity with the Son of God when he asked her to change her ways. She married many times.
There was a branch of the sect that was a charity in London, and the prophecy tells you that a fault was committed there. However, it was 'burnt by lightening' metaphorically, because the LORD predicted that when we came we would come like lightening. Where the building of the charity was, is very close to where I grew up in my teenage years. In fact, it is just around the corner from the funeral parlor, where all our family were taken.
The prophecy mentions the number 20 and that is the number of judgement. It is also the century that Jezebel built her organization internationally. ECP fell from her high place after the London property was sold and ECP's organization in the USA took the money. That property had been donated by a blessed man for the spiritual, and it had been left in his trust by a spiritual lady. The fault was committed in London, and the property was taken away from them.
The number given is '66'. In 1966, ECP's organization moved from Virginia to Colorado.  Her maiden name was also 'Wulf' and Jesus Christ gave a warning about the wolves. The information about the sect also relates to what happened to Jezebel and her followers in the time of Elijah. Hence, why the prophecy in Rev 2 mentions Jezebel. Christians are fully aware that it is Elijah that took on Jezebel, as such, the fact that the book of Revelation provided predictions about Jezebel also tells the people that the one that would overcome and be victorious would do what Elijah did, in as much as take them on in the name of the LORD. Hence, why in Rev 12, we were doing just that.
Twenty threes, also rhymes with decrees, that the book of Revelation tells them not to do.
We also warned the people about Camelot in the USA, we know what and why Camelot fell, it was to do with integrity. As we know the Queen of Camelot had an affair and then the kingdom fell into a wasteland. Even in this century, there are people that live the ancient legend, in the same old never ending karmic cycles. With all her power, ECP wasn't able to break her karmic cycle, because she did not heal herself.
This scholars link states the following regarding Theosophy. "
Many left the sect, and its belief system heavenly Father, many have done good. Let them be clear with clarity before they leave the planet. Share the truth with them so that their quest to know is over. Enliven them LORD to help with the mission with the children, and to build new jerusalem in your name, exactly as you planned it.. Bring them into your fold LORD, let them see your face, as you have shown it to me. Show them your righteousness, justice and mercy LORD, for your will to be done.