I've read it in a poem called "Olive Jar" by Naomi Shihab Nye. It's about the feeling of connection to the poet's Arab family and its culture. The man is a Israeli crossing guard. I think you gave me the right answer. Thank you so much for your replying.
And I add some of the stanzas which include the phrase I posted.
At the border an Israeli crossing-guard asked
where I was going in Israel.
<Excess quoted text deleted.>
Do you plan to speak with anyone? he said.
His voice was harder
and harder, bitten between the teeth.