True (γνησιω). Legitimate, not spurious. Old word from γινομα, but Pauline only in N.T. (Philippians 4:3; 2. Corinthians 8:8; Titus 1:4). In Philippians 2:20 the adverb γνησιως occurs and of Timothy again.

Christ Jesus (Χριστου Ιησου). So twice already in verse 1. Timothy 1:1 and as usual in the later Epistles (Colossians 1:1; Ephesians 1:1).