Still the standard for many in the South and how many older folks (including my grandparents) learned how to read
To be fair, the translation on Catholic.org (New American Bible version) states, "You shall not kill" and the Douay-Rheims, the standard in the Catholic Church from 1600 to the mid 20th century states 'Thou shalt not kill'.
For Old Testament translations it's wise to go to the source.