The verb εὐλογέω presents a noteworthy peculiarity in the development of its semantic range. In the Greek literature and documentary sources, it means "speak well", "praise" someone. In the Septuagint, however, there is a significant expansion. This verb becomes a standard translation equivalent of the Hebr. bārak, which means not only "praise" (with God as receiver), but also - and more frequently - "bless" (= pronounce words to confer special favour upon someone) with God as agent. These two meanings were inherited in the New Testament and later Christian literature and liturgy. There remained, however, some uneasiness about this usage. Exegetes (from Origen on) had to explain to their audiences the difference between the two meanings.
The same semantic difficulty is found in the two old biblical translations most relevant in Europe - Latin with benedicere and Ancient/Church Slavic with blahoslaviti. On the other hand, many modern translations do not use one-to-one correspondence (or calque equivalents), but have two different verbs for the two meanings. A problem arises when the literalist wing prevails.