I found this poem in the collection Philosophia Patrum edited by Julius Wegeler.
Non Spes, Sed Poena
Cum spes frustratur, non spes, sed poena vocatur;
Spes reficit dominum, fallit et ipsa suum.
The vocabulary is keyed to the DCC Latin Vocabulary list. There are two words in this poem that are not on the DCC list:
frustrō, frustrāre: disappoint, frustrate, fail
reficiō, reficere: repair, restore, rebuild
cum: with (prep. + abl.); when, since, although (conjunction + subj.)
dominus -ī m.; domina -ae f.: household master, lord; mistress
fallō fallere fefellī falsum: deceive
ipse ipsa ipsum: him- her- itself
poena -ae f.: penalty, punishment
spēs speī f.: hope
suus -a -um: his own, her own, its own
vocō -āre: call