Right, thanks for your concern, and I love that you're concerned mostly for the intruder. I am too.
First, our insurers, who specialise in church insurance, know that the church is unlocked night and day. We pay extra for it, but not extortionately - about 10% over a £2,000 (total cover) premium. You can get 25%, 50%, 75% and 100%, and it can be for a locked church, an 'open during the day and locked overnight' church or unlocked (if you'll excuse the expression) 24/7. We've gone for the full monty. When our tables were stolen from our unlocked church room, they paid out without question, even though it would have been not unreasonable for them to quibble. They didn't request that we locked the room either, though that would have been entirely reasonable.
Fire is a real anxiety in a church. There's a lot of wood; the pews, the roof timbers, quite apart from a rood screen, a reredos, the pulpit and lectern, any soft furnishings which might be used to start a fire. If a fire started, by arson or an electrical fault, it might go for hours before being seen. The walls themselves might survive but immense damage will have been done and ancient churches are listed at the highest level. Repairs would have to be done by specialists to the original specifications and the whole restoration would be a huge job. The stone walls would still stand, but they would be filthy and cracked, and do you remember the fires at York Minster and Windsor Castle? Restoration is an immense task.
It cost us £2,220 to heat and light the church and church rooms last year. We're not granted money, our regular congregation plus a trust fund (we're lucky there) paid for that, the insurance, the annual quota to the diocese that pays for our rector, the rectory and to fund the rector's retirement, as well as contribute to the cathedral's expenses. Et cetera. I have the accounts before me; we spent £41,000 in total last year (including donations to charity in this country and abroad) and there was a shortfall, we had to dip into our reserves. Please don't suggest that I'm unsympathetic to a homeless person, but heating that's normally on for 5 hours a week to be, without my knowledge (it's my responsibility as churchwarden) or permission, turned on every night for a total of anything from 50 to 100 hours a week can not be ignored. If someone came into your garden and drained the heating oil out of your tank, you'd call it theft. If someone tapped into your electricity supply and used ten times more than you did, but it went on your bill, you'd say he'd stolen it. As I said before, if he has worked out how to get into the extension where the heating controls are kept, he could go into another room which is heated to an acceptable overnight level (we don't want pipes to freeze and it's used several times a week) and we'd not know. If I wondered, I'd choose not to know.
Having said that, if I'd gone down tonight, as I did with the Fellow, and found a homeless person, I don't believe you'd think we'd have turned him away. I'd have explained, offered him the church room for the night, taken him breakfast in the morning and then spent as much time as was needed in helping him. There are shelters for the homeless in Lowestoft and Norwich - I'd take him there, but a local man might not want to go. There is a village charity that could give money. The Fellow and I went along just before 7 pm, and no one was there. I have turned off the boiler in the boiler house and he can't turn it on again. However, as we are both very concerned to think that someone might be cold tonight, I have left a note with my phone number. If he rings, I'll do all I possibly can to help, short of letting him into my home. I don't trust him, he's a thief. The Good Samaritan helped a traveller who had fallen among thieves.
Oh, and Dave (the Fellow) and I had a chat. "Do we need to spread this around?" I said. "Well, who needs to know?" he replied. "If people knew, they would get worried and want to lock the church." "I wouldn't want to turn anyone away."
So please, darlings, don't spread it around, because we are praying for this man (a woman would be better placed to receive help). He'll get help if he is able to stretch out his finger. I sort of don't expect to know how this ends.