Charles Ellicott Commentary Jude 1:20-21

"But ye, beloved, building up yourselves on your most holy faith, praying in the Holy Spirit, keep yourselves in the love of God, looking for the mercy of our Lord Jesus Christ unto eternal life." — Jude 1:20-21 (ASV)

An exhortation to strengthen yourselves in the faith by prayer, godliness, and hope.

(20) But you, beloved. This is exactly as in Jude 1:17: “you” is in emphatic contrast to these sensuous and unspiritual men.

Building up yourselves. This means making yourselves firm on the sure foundation of faith, in contrast to those “who separate,” and imagine themselves firm in their impious notions. The idea is not so much that of increasing and completing a building as of strengthening its foundations.

Faith and its object are here almost identified. To have faith as one’s foundation is the same as having Christ as one’s foundation. This is “Your faith,” that which has been “once for all delivered” to you (Jude 1:4). This is also “Most holy faith,” as opposed to the most unholy quicksands of the doctrines condemned in this Epistle.

Praying in the Holy Ghost. Only in this way can Christians make their foundation firm. The Greek text allows for “in the Holy Ghost” to be connected with the previous clause, but our translation is preferable. The expression “praying in the Holy Ghost” is not found elsewhere. It means that we pray in His strength and wisdom: He moves our hearts and directs our petitions. (See Notes on Romans 8:26.)

Keep yourselves in the love of God. This means not our love for God, but His love for us. Consequently, it is not that the three great Christian virtues—Faith, Hope, and Charity—are taught here, although at first sight we might be tempted to think so. God’s love is the realm in which those who are built up on faith, and supported by prayer, can continually dwell.

The mercy of our Lord Jesus Christ. This refers to the mercy He will show as Judge at the Last Day. Through prayer in the Spirit, we are kept in the love of the Father for the mercy of the Son.

Unto eternal life. These words can be connected either with “keep yourselves,” with “looking,” or with “mercy”; it is best to connect them with “keep yourselves.”