What is the reason for this (house lit up)

Why don't you just ask?

It probably is because of Diwali, which began yesterday.
In the area where I lived until recently, many of the Hindu families decorated their houses this way for several days when there was a family wedding taking place or some other significant celebration, e.g. A 90th birthday or similar.

Diwali is 19th to 23rd October this year so the lights are maybe for that. It's the Hindu festival of light.

Divali, I should think. However, round our way it is getting very popular to have white fairy lights somewhere in your front garden all year round. I like it. What I do find annoying are the very bright orange security lights that some householders seem to think are essential to protect themselves from wrongdoers. These lights also come on when cats or foxes or even pigeons are within their range, which can be very annoying if they are aimed at your bedroom window and wake you up.

I have white fairy lights in my back garden all year round,I love christmas lights an dhated taking them down.The place always looks so dark and dismal without lights ,so I decided to get white ones and leave them up .I think they look great

Oh dear, that reminds me of many years ago when I bought our first outdoor Christmas lights and festooned a pyracantha outside the front door.
A very good friend who lives two houses away rang me about something (yes we are that lazy) and I told her that I had been putting up outdoor lights. Where? She asked.
What possessed me to refer to the Pyracantha as “my bush”I will never know till the day I die. There was a silence then I heard a choking sound and her shouting “Tony, you’ll never guess where Maw has hung her fairy lights”!,
I still get teased about walking funny as Christmas approaches.

We saw a very large detached house, covered in cascading white lights, when we were on our way to a lecture. DH thought it a bit early but I thought it was probably for Diwali. I have never seen so many lights on one house, could not even see the front door.

Wow. Sounds lovely. I've never seen houses lit up for Diwali before. Is this a new thing or just one that hasn't seemed to catch on near us?

I think the popularity is probably due to the availability of relatively inexpensive LED light strings.

I think it likely that it s linked to celebrating Diwali too.

Has anyone had the thought that when you espy an early Christmas decoration / tree - it might just be because someone is terminally ill and knows they won't see the next Christmas so they may be getting in an early 'celebration'?

Maw, thank you for my first giggle of the day!

Oh maw it was you you had lights in her bush not phoenix ?. I remember that Christmas thread from years ago it was sooo funny. (Sorry phoenix case of mistaken identity )

A few years ago when he was taking down the Christmas decorations I mentioned to The Wonderful Man that he'd forgotten the (white) fairy lights around the hall mirror - he said he liked them so much he decided they should stay. Now I would hate not to have them, they're so cheery at this time of year and provide a softer light than the ceiling fixture.

Diwali is the Festival of Lights remembering when Rama returned home after defeating the ten headed demon Ravenna and all Rama’s people welcomed him home by lining the roads with little lights (divas). In India all faiths put up their lights for Diwali (and for everyone else’s festival). An acquaintance (a Christian) died when he fell off his garage putting up Diwali lights.

I did wonder if it was for Diwali (apologies for my incorrect spelling in the OP - I must learn not to post without wearing reading glasses!), but then I thought if that was the case, surely there would be lots more similarly well lit houses.

The house looks absolutely gorgeous with these strings of white lights going from the roof to the ground.

Petra - I went past quite late at night, and didn't think they would appreciate a stranger knocking at their door and asking what the lights are for. I know I wouldn't! If I go past the house again and there is someone in the garden, I will stop and ask.

I spoke to a friend who said that someone in their street had their house similarly decorated earlier this year, so she thought it was unlikely to be for Diwali. She said that it was for a Shaadi wedding, and when I googled that, the images returned do look very similar to the house near me.

I hope I do get the chance to speak to the home owner, because I would love to know more about this tradition and why they do it. Is it both bride and groom's homes? How long do they stay up for? What do they represent? So many questions to ask

(And I am giggling like an immature thing at an immature thing's reunion at Maw's lit up bush!!!)