In Judges 7, verse 5, the NRSV renders, "All those who lap the water with their tongues, as a dog laps, you shall put to one side; all those who kneel down to drink, putting their hands to their mouths, you shall put to the other side.'
A comparison of the NRSV rendering to the various Hebrew base text, does not show the phrase "putting their hands to their mouths" occurring in verse 5, but rather, verse 6 (where the NRSV leaves it out - yet the Hebrew places the words 'putting their hands to their mouths' after the word 'lapped' in verse 6).
It would also appear that the phrase "you shall put to the other side" does not find support in the Hebrew in verse 5, nor in any verse prior or subsequent (likely a dynamic license in place of "likewise" or "also") The NRSV has apparently inserted the phrase "putting their hands to their mouths" into verse 5 from 6, and has added as a bolt from the blue "you shall put to the other side".Most other translations remain loyal to the underlying Hebrew and render "All those who lap the water with their tongues, as a dog laps, you shall put to one side; likewise (or also) all those who kneel down to drink"
In verse 5, the Hebrew (BHS and WLC base text) reads, "Yarad'am mayim Yhwh 'amar Gid`own laqaq mayim lashown keleb laqaq yatsag kara` berek shathah" It is not until verse 6 in which the phrase "yad peh" (hand to the mouth) appears in the Hebrew base text.The NRSV is not known for its bolts from the blue as is the NIV and a few other dynamic translations – so their removal from verse 6 and placement to verse 5 was likely based on a textual variant, or some other indicator, which the committee was convinced adequately justified a departure from the base text.
Unfortunately, the NRSV (at least that I can find) does not notate or otherwise explain the departure.As far as the indications of why the lappers from their hands were chosen over those who got down to the water level to drink? Take your pick – Rabbinical tradition holds that the lappers were chosen because they refused to bow down to an idol (see Tanhuma – Buber; Toledot 19; Yalqut Shim'oni, Judges 62:1 and 1 Kings 29. On the other hand – Josephus (Antiquities V.vi.3, 216-217) claims that the lappers were the cowards, scared to turn their backs kneel and drink, supposedly highlighting an even more important victory miracle by choosing cowards.