What did Jude mean when he said to "keep yourselves in the love of God?" (Jude 21)

Jude 20-21 King James Version (KJV)
20 But ye, beloved, building up yourselves on your most holy faith, praying in the Holy Ghost,

21 Keep yourselves in the love of God, looking for the mercy of our Lord Jesus Christ unto eternal life.

Clarify • Share • Report • Asked January 22 2020 • Jack Gutknecht