Adam Clarke on Numbers 1:14

Eliasaph, the son of Deuel - This person is called Reuel, Num 2:14. As the ד daleth is very like the ר resh, it was easy to mistake the one for the other. The Septuagint and the Syriac have Reuel in this chapter; and in Num 2:14, the Vulgate, the Samaritan, and the Arabic have Deuel instead of Reuel, with which reading a vast number of MSS. concur; and this reading is supported by Num 10:20; we may safely conclude therefore that דעואל Deuel, not רעואל Reuel, was the original reading. See Kennicott. An ancient Jewish rabbin pretends to solve every difficulty by saying that "Eliasaph was a proselyte; that before he embraced the true faith he was called the son of Reuel, but that after his conversion he was called the son of Deuel." As Reuel may be translated the breach of God, and Deuel the knowledge of God, I suppose the rabbin grounded his supposition on the different meanings of the two words.