Genesis 17
Young's Literal Translation (YLT)
25 and Ishmael his son `is' a son of thirteen years in the flesh of his foreskin being circumcised;
World English Bible (WEB)
25 Ishmael, his son, was thirteen years old when he was circumcised in the flesh of his foreskin.
Bible in Basic English (BBE)
25 And Ishmael, his son, was thirteen years old when he underwent circumcision.