Albert Barnes' Notes on the Whole Bible - Joshua 5:2
Make thee sharp knives - Render rather as marg., and compare marginal reference and note. Knives of flint or stone were in fact used for circumcision, and retained for that and other sacred purposes, even after iron had become in common use. The rendering of the margin is adopted by almost all ancient versions, by most commentators, and by the fathers generally, who naturally regarded circumcision performed by Joshua and by means of knives of stone or rock, as symbolic of the true circumcision... read more
The Pulpit Commentary - Joshua 5:4
After they came out from Egypt. Rather " on their journey from Egypt." See next verse, where the same words are translated "as they came out." read more