Louw was born in Johannesburg, South Africa on 31 December 1932. He matriculated in 1949 at the Hoërskool Helpmekaar in that city. In 1952 he completed a bachelor's degree cum laude at the University of Pretoria, South Africa, majoring in Greek, Hebrew and Sociology. This was followed by a master's degree cum laude in 1954. The title of his thesis was "Die κατοχή in die Memphis papyri" ("The κατοχἠ in the Memphis papyri").
He held the post of lecturer at the University of the Orange Free State Bloemfontein, South Africa, in 1954, becoming the head of the department of Greek at this university in 1966. In 1956 he married Rina Watson. Three children were born from this marriage. He completed his doctoral studies at the University of Pretoria in 1959, with a dissertation entitled "A study of μἠ with the Present Imperative and Aorist Subjunctive". From 1973 to 1992 he was head of the department of Greek at the University of Pretoria. After retiring in 1992, he and Rina moved to Herolds Bay, on the Cape South Coast of South Africa. He died in Pretoria on 23 December 2011. He studied abroad in 1961 (University of Utrecht, Netherlands) and 1971 (Ohio State University, Columbus, Ohio). In 1987 Princeton University offered him a four-year appointment as head of a newly established Translators' Institute. Louw declined, because of political pressure.
Louw remained active retirement. He was a collaborator on the reference Bible being prepared by the Bible Society of South Africa, and was the main translator of the ScriptureDirect Interlinear Greek Bible translation of the New Testament that is available as an app in different formats. - From Wikipedia