The ways of the religious can seem strange to the non-practising but there is probably nothing stranger than an eruv. How do you explain that a boundary marked in places by a pair of poles linked by near-invisible wire can convert a chunk of city into notional “private” space so that Jews can carry things within it on Shabbat? Many Jews find it hard to fathom, never mind non-Jews.

Unsurprisingly, British Jewry, not given to drawing too much attention to itself, did not go in for eruv building until recently. When the first metropolitan eruv was launched 21 years ago, covering a significant area in north-west London, it was transformative, liberating in particular young buggy-pushing parents. Its creation signalled a new self-confidence and its success inspired others; there are now more than a dozen eruvim operating across the country.

So normal a part of the Anglo-Jewish landscape have eruvim become that it’s easy to forget how controversial the first initially proved. It took more than a decade from initial planning to the erection of the first poles. Objections poured into the local council. Some liberal Jews feared that the device would encourage a “ghetto” mentality. Secularists decried the intrusion of religious apparatus into the public square.

Once up, the poles were pretty unobtrusive, blending into the existing street lamps and signs. You probably wouldn’t notice them unless you were deliberately looking for them. Nevertheless, they were a visible declaration of Jewish presence.

Over time, the opposition began to melt away, if it did not die down altogether. One argument against eruv applications was that they posed a potential threat to wildlife – yet no avian casualties have been recorded, nor decapitated bats.

But some of the fiercest resistance came from the Orthodox right. Although the north-west London eruv was under the supervision of the impeccably Orthodox head of the London Beth Din at the time, Dayan Chanoch Ehrentreu, other rabbis within the steibl belt felt it was not kosher enough and would not permit their followers to use it. Use of the eruv became a dividing line between streams of Orthodoxy.

And yet even the implacably conservative Union of Orthodox Hebrew Congregations finally bowed to gathering demand, giving its blessing in 2021 to an eruv that serves part of Stamford Hill. Undoubtedly, the experience of lockdown during the pandemic played its part in concentrating rabbinic minds, when young families otherwise faced being confined to small apartments over Shabbat.

Some Stamford Hillniks feel the eruv does not go far enough and would like a wider perimeter to benefit more in the neighbourhood.

On the other hand, there have been murmurs of disapproval from frummer-than-thou diehards who think the new enclosure an unwelcome concession.

In the first months, one saboteur, a phantom snipper, would sneak out in the dead of night with a pair of cutters and try to disable it by severing the wire. But even those in holy Golders Green who until now have not made use of the London Beth Din eruv are soon to get their very own. It is being built to the exacting specifications of the spiritual head of the Federation of Synagogues, the resourceful Rabbi Shraga Feivel Zimmerman, a former Rav of Gateshead. If there was such a thing as a glatt-kosher eruv, then this would be it.

Whereas wire-linked poles have become a familiar aspect of eruv design, representing symbolic gateways, the Golders Green eruv is even more elaborate in that it will also consist of symbolic doors in various locations – green cabinets that resemble electricity boxes. These contain flexible barriers that can be rolled out to seal off a road. As far as I understand, this might be done only once a year and in the early hours of the morning to prevent inconvenience to traffic.

It is a sign of change that whereas the inaugural eruv faced a planning battle, the new Golders Green Eruv went through almost on the nod. And now the elders of Gateshead are consulting about establishing one in the Tyneside yeshivah town after a community survey indicated strong support. A local source told me it would be a “landmark” development.

While some in the community may still think the concept of an eruv mad, more generally there is a pragmatic acceptance of something that makes life easier for people.

The eruv boom tells a story of quiet progress. It is a long-term investment in Jewish life.

The good folk of Gateshead are building for their future.