The poem
Fishermen at Ballyshannon Netted an infant last night Along with the salmon. An illegitimate spawning,
A small one thrown back To the waters. But I'm sure As she stood in the shallows Ducking him tenderly
Till the frozen knobs of her wrists Were dead as the gravel, He was a minnow with hooks Tearing her open.
She waded in under The sign of the cross. He was hauled in with the fish. Now limbo will be
A cold glitter of souls Through some far briny zone. Even Christ's palms, unhealed, Smart and cannot fish there.

This is a fascinating look at infanticide at the hands of the church. In making it so taboo to have a child out of wedlock, the church and local gossip has driven many a mother to drown her own. Even Christ would not withstand these stinging waters. I think Heaney does a superb job at illustrating the woman's pain with the line about the fish hooks tearing at her as she commited the ultimate crime.
Luckily, the concept of limbo (where unbaptized babies went to wait eternally, since they couldn't get into heaven) has been abolished by the German pope now, I meant to say. Interesting concept in the poem about the woman baptizing her child herself. Makes you wonder if she was able to go on or if she herself might have drowned too. And what were the fishermen saying and feeling? Something like, "Oh what a pity?"