I am baffled by our translations of the Lord’s Prayer passage in Luke, and maybe you join me here. Luke 11:2, in the NIV, RSV, NRSV, and many others: “When you pray, say.” Even the ESV, which prides itself on a more literal rendering, has the same. “When you pray, say.” The Greek behind our translations is hotan proseucheisthe legete, which, if the translations would be a little more literal, would be “whenever you pray, recite/say.”

Which is exactly what we find in both John Nolland‘s commentary on Luke and Joel Green‘s commentary. B.S. Easton‘s very old commentary from 1926 has this: “Lk understands that the Lord’s Prayer should form part of all Christian devotions (translates “whenever”)” (175). Fitzmyer‘s majestic commentary has this observation: “the Lucan formulation presents the ‘Our Father’ as the mode of all Christian prayer, whereas the Matthean gives it merely as an example” (902).
Darrell Bock brings us, correctly, back to Easton: “Jesus’ response is important for the life of today’s church, since some reject the use of liturgical prayer. In saying ‘when you pray say…,’ Jesus endorses the communal and liturgical function of the prayer ([pointing out that the hotan “anticipates the prayer’s repetition”)” (1050).
Here we have then a litany of commentaries, all the standard ones, saying one thing (translate it “whenever you pray, say” the Lord’s Prayer) and a litany of translations saying another thing (translate it “when you pray, say”). The grammar clearly means “whenever you pray [together], you should say/recite the Lord’s Prayer.”
Why is it that so many translations omit the “ever” after “when”? Why is that “say” is used instead of “recite” — for the term “recite” is what is in mind if one is to say this very prayer whenever one prays.
I can guess. Part of it could be non-liturgical propensities, but this doesn’t explain the versions that stem from liturgically-shaped communities. Part of it could be discomfort with the sheer baldness and boldness of Jesus: whenever you pray, I want you to say this prayer. That seems a little too often, some translators might think. I’m not sure why it is this way, but there isn’t much reason for translations to ignore every good commentary we have.
To support the commentaries, and to bring in something none of them discusses adequately, the disciples come to Jesus and ask “for a prayer” as John had given his followers a prayer. “Teach us to pray,” they ask. Jews at the time of Jesus, and much before his day and still to this day, pray three times a day: sunup, midday, and evening prayers. Jews begin and end the day with the Shema, and 2-3 times a day (during Jesus’ day, so far as we can tell) said/say/recite the Amidah — a prayer of 18 benedictions. The Lord’s Prayer, as far as we can judge the evidence, replaced the Amidah for the Jewish followers of Jesus. Didache tells us the early Christians repeated the Lord’s Prayer 3x/day. Just as Jesus told them: “whenever you pray, recite the Lord’s Prayer.”
Because Jesus’ answers the questions of the disciples by giving a “prayer to recite,” I believe their question was asking for that. In other words, I’d translate Luke 11:1 like this: not “Lord, teach us to pray” but “Lord, give us a prayer.” Translation requires sensitivity to context, to historical context, and to logical flow.
Whatever the reasons, and I’d be happy to hear your suggestions, the translations have this one wrong. The correct translation is: “whenever you pray, say/recite.” Jesus is here clearly commanding his followers to say the Lord’s Prayer, that is to recite it aloud, whenever (all the time) they pray, and he might be thinking especially of communal prayer. But, the text’s translation is not open to dispute.