What does John 17:7 mean?

A large portion of Jesus' lessons to the disciples was demonstrating His divine nature (John 2:11; 14:11; Mark 4:41; Matthew 16:13–17). While these men don't fully grasp all that is about to happen (John 12:32–34), they seem fully convinced that Jesus is the Promised One, and what He teaches them comes directly from God (John 5:36; 10:29; 12:49).

In this portion of the High Priestly Prayer (John 17:1), Jesus is praying for His closest followers, often referred to as the Twelve (Matthew 26:14; Mark 6:7; Luke 9:1; John 6:67). One of these men, sadly, has chosen disobedience and damnation (John 17:12), but the others chose to "keep [God's] word" (John 17:6). Earlier this same evening, Jesus warned about impending persecution (John 16:1–4), while also speaking comfort about the role of the Holy Spirit (John 16:13–14). This part of His prayer focuses on the apostles and their ability to remain faithful despite the hard times to come.