Albert Barnes Commentary 2 Timothy 1:8

"Be not ashamed therefore of the testimony of our Lord, nor of me his prisoner: but suffer hardship with the gospel according to the power of God;" — 2 Timothy 1:8 (ASV)

Be not thou therefore ashamed of the testimony of our Lord. Do not be ashamed to bear your testimony to the doctrines taught by the Lord Jesus (John 3:11, 32, 33; 7:7).

(20:24; 1 Corinthians 1:6; Revelation 22:16). Paul seems to have perceived that Timothy was in some danger of being ashamed of this gospel, or of shrinking back from its open avowal in the trials and persecutions to which he now saw this gospel exposed Timothy.

Nor of me his prisoner. Of the testimony which I have borne to the truth of the gospel. This passage proves that, when Paul wrote this epistle, he was in confinement (6:20; Philippians 1:13, 14, 16; Colossians 4:3, 18; Philemon 1:9).

Timothy knew that Paul had been thrown into prison on account of his love for the gospel. To avoid that himself, there might be some danger that a timid young man might shrink from an open avowal of his belief in the same system of truth.

But be thou partaker of the afflictions of the gospel. The sufferings to which the profession of the gospel may expose you .

According to the power of God. That is, according to the power which God gives to those who are afflicted on account of the gospel. The apostle evidently supposes that those who were subjected to trials on account of the gospel might look for Divine strength to uphold them, and asks Timothy to endure those trials, relying on that strength, and not on his own.