This Epistle is the last testament and swan-like death song of Paul [BENGEL]. according to the promise of life . . . in Christ--Paul's apostleship is in order to carry into effect this promise. Compare "according to the faith . . . in hope of eternal life . . . promise," &c. (Tit 1:1-2). This "promise of life in Christ" (compare Ti2 1:10; Ti2 2:8) was needed to nerve Timothy to fortitude amidst trials, and to boldness in undertaking the journey to Rome, which would be attended with much risk (Ti2 1:8).