Instructions for running a church: who may lead, how widows are enrolled, what to do about disputes. It assumes an institution with procedures, which is the main reason most scholars date it after Paul.
What the book is
1 Timothy is addressed to a younger colleague left in charge at Ephesus. It warns against speculative teaching, gives instructions on prayer and on the conduct of men and women in assembly, lists qualifications for overseers and deacons, sets rules for enrolling widows and for paying elders, and closes with instruction about wealth.
It is administrative rather than argumentative. Where Romans builds a case, this book issues procedures.
How it is put together
The material is arranged by topic rather than by argument, and it moves between subjects without transition. Several short formulaic passages read as quotations of existing material, introduced by a phrase marking them as trustworthy sayings.
It belongs with 2 Timothy and Titus to the group conventionally called the Pastoral Epistles, which share vocabulary, concerns and outlook and are almost always treated together.
The authorship question
The majority of critical scholarship holds that Paul did not write the Pastorals, and the arguments are cumulative rather than decisive individually.
The vocabulary differs sharply from the undisputed letters: a large proportion of the words do not appear elsewhere in Paul, and many that do appear are used differently. The church structure assumed — a settled order of overseers, deacons and enrolled widows with entry qualifications — reads as later than the fluid situation of 1 Corinthians. Faith appears as a body of doctrine to be guarded rather than as trust. The itinerary implied does not fit the movements known from Acts and the other letters.
The defence answers that vocabulary counts on small samples are weak, that a different genre and a different addressee explain much of the difference, that Paul’s later years are not covered by Acts and so cannot be checked, and that a secretary given wide latitude could account for the rest.
Dating follows from the answer: the mid-sixties CE if Paul wrote it, or somewhere between about 80 and 110 CE if he did not.
Where the external record touches it
The manuscript record is the substantive external evidence, and it is ambiguous. P46, the earliest substantial collection of Pauline letters, does not contain the Pastorals — but the surviving codex is incomplete at the end, so the omission may be an accident of preservation rather than a statement about the collection.
The Muratorian fragment, a list of accepted books usually dated to the later second century though sometimes placed later, includes all three Pastorals. Marcion’s collection, from the mid-second century, did not.
Ephesus itself is extensively excavated, but nothing in the archaeology bears on the letter’s contents.