This is possibly the most POD thing Seamus Heaney has ever written.

The Biretta

Like Gaul, the biretta was divided
Into three parts: triple-finned black serge,
A shipshape pillbox, its every slope and edge
Trimly articulated and decided.

Its insides were crimped satin; it was heavy too
But sported a light flossy tassel
That the backs of my fingers remember well,
And it left a dark red line on the priest's brow.

I received it into my hand from the hand
Of whoever was celebrant, one thin
Fastidious movement up and out and in
In the name of the Father and of the Son AND

Of the Holy Ghost... I placed it on the steps
Where it seemed to batten down, even half-resist
All the brisk proceedings of the Mass -
The chalice drunk off and the patted lips.

The first time I saw one, I heard a shout
As an El Greco ascetic rose before me
Preaching hellfire, Saurian and stormy,
Adze-head on the rampage in the pulpit.

Sanctuaries. Marble. Kneeling boards. Vocation.
Some made it looked squashed, some clean and tall.
It was as antique as armor in a hall
And put the wind up me and my generation.

Now I turn it upside down and it is a boat -
A paper boat, or the one that wafts into
The first lines of the Purgatorio
As poetry lifts its eyes and clears its throat.

Or maybe that small boat out of the bronze age
Where the oars are needles and the worked gold frail
As the intact half of a hatched-out shell,
Refined beyond the dross into sheer image.

But in the end it's as likely to be the one
In Matthew Lawless's painting, The Sick Call,
Where the scene is out on a river and it's all
Solid, pathetic and Irish Victorian.

In which case, however, his reverence wears a hat.
Undaunting, half domestic, loved in crises,
He sits listening as each long oar dips and rises,
Sad for his worthy life and fit for it.

Like Gaul, the biretta was divided into three parts... What a suprising way to start! Good poetry sneaks up and clobbers you like that. The conceit of the biretta being a boat - it seems arbitrary, based solely on the shape, but Heaney pulls all sorts of meaning out of it.