Bid co h-eistechtach cailli...

Bid co h-eistechtach cailli,
bid co féchsanach muigi,
oir ní fedrais, mór in mod,
nach biad t' escara it fharrad.

(be * hearingful * of forest /
be * watchful * of plain /
for * not * you know - great * the * deed /
that not * would be * your * enemy * in your * presence)

Keep your ears open in the forest
and your eyes open on the plain,
for you don't know -- this is important --
whether your enemy is near.

This is the eleventh stanza in the poem "Fionn's Advice to Mac Lugach" at the beginning of "Acallam na Senórach". See also "Dá trian do mhíne re mnáibh" in this collection.