What does it mean that in this we groan?
It means believers cannot fully comprehend their eternal prospect and earnestly long to be clothed upon with their house from heaven—that is, the new body. This groaning expresses desire for the heavenly dwelling place and new body, not mere complaint.
Les explains that “in this we groan” means we just cannot fully comprehend, while earnestly desiring to be clothed upon with our house, or dwelling place, which is from heaven—in other words, the new body. This fits the earlier prospect that believers are heavenly, will rule with Christ in the heavenlies for eternity, and will not be limited by time and space. Les also points to Philippians 3:20–21 when answering questions about what kind of body we will have in the eternal.
For in this we groan, earnestly desiring to be clothed upon with our house which is from heaven: