For I am suffering these things [See verse 8] for this reason [i.e., because of being a Gospel preacher]. Yet I am not ashamed because I know whom I have believed in [i.e., Jesus], and I am convinced that He is able to guard what I have entrusted to Him [i.e., Paul's spiritual well-being] until that day [i.e., the day of judgment].

Paul, an apostle of Christ Jesus by God’s will, for the promise of life in Christ Jesus:

But the Lord stood by me and strengthened me, so that through me the message could be fully proclaimed and that all the Gentiles could hear it. And I was rescued from the lion's mouth. [Note: This is probably a figure of speech indicating that Paul had escaped some immediate danger. See Psa. 22:20-21].