The Second Epistle of Paul to Timothy, usually referred to simply as Second Timothy and often written 2 Timothy, is one of the three Pastoral Epistles traditionally attributed to Saint Paul, and is part of the New Testament.
The International Standard Bible Encyclopedia affirms Paul's authorship and documents the fact that a vast majority of the early church fathers attest to Paul's authorship of all the pastoral epistles. Most conservative biblical scholars agree.
However, many modern biblical scholars argue that 2 Timothy was not written by Paul but by an anonymous follower, after Paul's death in the First Century.