Approaching 5.00 p.m. on a cool, windy summer afternoon, Emmy and I join a queue filing into Westminster Abbey for the daily Evensong service. Vergers usher us to places in a block of folding chairs at the junction of the nave and transepts (called “the theatre”) under columns of time-polished stone that disappear into the ornate, peaked-arch roof more than 30 metres above us.

Westminster Abbey's interior hushes you and compels you to look upwards. (Wikipedia open-access image)

The ambience imposes a kind of hush. The vergers in black capes with bright red collars stride silently back and forth, pointing, whispering, bobbing. A group of teenagers wearing “I ❤ NY” tee-shirts sits nervously exposed in the front row. One of them pulls the ear bud of an iPod from his ear and hurriedly stuffs it into his shirt pocket. Three tiny Japanese ladies sit with smooth upturned faces, open-mouthed and silent. An old bent woman in a grimy gabardine overcoat comes by pushing a walking frame. A small squad of beefy, crew-cut young men, wearing white dog-collars of the priesthood, point and nod and murmur in German. A young tourist tries to cram her backpack into the space under her chair as if she is settling into an airline seat.

Exactly at five o’clock a very high, thin, scarcely audible note beams like a laser from the organ. Slowly it swells and cascades into a complex glissando. It is joined by a pitchless rumbling from deep in the stomach of the organ, and the space between upper and lower registers is filled in with a quiet but intricate play of melody. The effect is ethereal, an ornate structure of glittering sound filling the air like an audio-abbey.

The theme of the service is Abraham’s unwavering faith. He is a model of the obedient believer, willing to personally sacrifice his own son if God asks this of him. The presiding priest tells the story in a curiously matter-of-fact tone:

And they came to the place which God had told him of; and Abraham built an altar there, and laid the wood in order, and bound Isaac his son, and laid him on the altar upon the wood. And Abraham stretched forth his hand, and took the knife to slay his son. And the angel of the Lord called unto him out of heaven, and said ‘Lay not thine hand upon the lad, neither do thou any thing unto him: for now I know that thou fearest God.

The narrowly avoided sacrifice presages a later sacrifice that goes ahead uninterrupted. The choir celebrates it in a long, complex and beautifully exuberant anthem.

The Paschal Lamb is offered, Christ Jesus made a sacrifice for sin. The earth quakes, the sun is darkened, the powers of hell are shaken, and lo he is risen up in victory.

The fading sun – dyed purple and bright yellow from its passage through distant reaches of stained glass – slants across the congregation. The versicles and responses are intoned in a high, half-spoken half-sung monotone, passing back and forth between the priest and choir.

O Lord save thy people
And bless thine inheritance
Give peace in our time, O Lord
Because there is none other that fighteth for us, but only Thou O God

For once, I’m finding it hard to be unmoved. Evensong at Westminster Abbey is a confusing experience. I cannot be the snarling, sabre-toothed atheist I would like to be.

But equally I cannot quiet the thought that Evensong – with the power of the ambient architecture, the power of the words, the power of the music – is largely (but not entirely) about stifling understanding in the interests of privilege. With a rush of pure beauty the choir sings:

He hath put down the mighty from their seat
And hath exalted the humble and meek.
He hath filled the hungry with good things
And the rich hath he sent empty away.

I look around. Everything in the Abbey contradicts – even mocks – these words. Of the many hundreds of thousands of hands that shaped the stones, painted the windows, chiselled the ornate woodwork and worked high above the ground hanging from flimsy scaffolding, not one is represented, let alone named, in the inscriptions and busts and reliefs that crowd the walls and floors of the building. And this in a building in which the words “he hath exalted the humble and meek” can resound with such mesmerising harmony.

And behind the ancient story of Abraham’s near-miss murder of his son – with its metaphors of unwavering obedience, sacrifice and redemption through death – lies an unspoken, and probably wholly unnoticed, but very modern lesson: fundamentalism, fanaticism, terrorism and war find their deepest roots in stories like this.