No soldier on service (ουδεις στρατευομενος). "No one serving as a soldier." See 1. Corinthians 9:7 for this old verb and 2. Corinthians 10:3; 1. Timothy 1:18 for the metaphorical use.
Entangleth himself (εμπλεκετα). Old compound, to inweave (see Matthew 27:29 for πλεκω), in N.T. only here and 2. Peter 2:20. Present middle (direct) indicative.
In the affairs (ταις πραγματειαις). Old word (from πραγματευομα, Luke 19:13), business, occupation, only here in N.T.
Of this life (του βιου). No "this" in the Greek, "of life" (course of life as in 1. Timothy 2:2, not existence ζωη).
Him who enrolled him as a soldier (τω στρατολογησαντ). Dative case after αρεση (first aorist active subjunctive of αρεσκω, to please, 1. Thessalonians 2:4, purpose clause with ινα) of the articular first aorist active participle of στρατολογεω, literary Koine word (στρατολογος, from στρατος and λεγω), only here in N.T.