“Beloved, while I was very diligent to write to you concerning our common salvation, I found it necessary to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints.”
I found it necessary to write to you
Something came up so that Jude found it necessary to urgently warn his readers about apostasy and the need to “earnestly contend for the faith.” It was a necessity because there is no option but to attack apostasy when it raises its ugly head.
exhorting you to contend earnestly
The words “contend earnestly” relate to the English word agony. This is an athletic term or military term for vigorous combat and struggle. The fundamental tenets of the faith were under attack and strenuous effort was required to defend them; therefore, Jude exhorted or challenged his readers about indifference to those distorting the truth. His readers did not want to get involved in controversy by standing up for the faith. They wanted peace at all costs, even the cost of truth. They understood the gospel but they would not take a stand on it, so Jude rebuked them for their unconcern. Both comfort and rebuke are expressions of love.
for the faith
“The faith” is something completely different than “faith.” “The faith” here is the content of what we believe, not the act of believing. “The faith” then is God’s special revelation in written form—the whole realm of divine doctrine. The word “the” before “faith” conveys that a recognized body of doctrine is at stake—apostolic teaching found especially in the New Testament.
which was once for all delivered to the saints.
“The faith” was delivered at one point in the past to the saints. The word “delivered” carries the idea of being entrusted with the faith. The faith about which Jude writes was “once” delivered or handed down to the saints. This was a once-for-all salvation. There is no further word to say on this subject. Should any add to this salvation, it is out of bounds. “The faith” consists of New Testament “doctrine.”
But God be thanked that though you were slaves of sin, yet you obeyed from the heart that form of doctrine to which you were delivered. Ro 6:17
Christians must stand alert to deviation from sound doctrine.
We must come to grips with the fact that we need to defend the faith. There is a faith once for all delivered to the saints that we must maintain. We can add nothing to it. It is not something that we discover for ourselves but it was handed down by revelation. Therefore, we need to go for an all-out defence of the faith (“contend earnestly”).
I tell you that He will avenge them speedily. Nevertheless, when the Son of Man comes, will He really find faith on the earth? Lk 18:8
Then the word of God spread, and the number of the disciples multiplied greatly in Jerusalem, and a great many of the priests were obedient to the faith. Ac 6:7
But what does it say? “The word is near you, in your mouth and in your heart” (that is, the word of faith which we preach)… Ro 10:8
Watch, stand fast in the faith, be brave, be strong. 1 Co 16:13
Examine yourselves as to whether you are in the faith. Test yourselves. Do you not know yourselves, that Jesus Christ is in you?—unless indeed you are disqualified. 2 Co 13:5
But they were hearing only, “He who formerly persecuted us now preaches the faith which he once tried to destroy.” Ga 1:23
But before faith [content] came, we were kept under guard by the law, kept for the faith [content] which would afterward be revealed. Therefore the law was our tutor to bring us to Christ, that we might be justified by faith [act of believing]. But after faith [content] has come, we are no longer under a tutor. Ga 3:23-25
…if indeed you continue in the faith, grounded and steadfast, and are not moved away from the hope of the gospel which you heard, which was preached to every creature under heaven, of which I, Paul, became a minister. Col 1:23
As you therefore have received Christ Jesus the Lord, so walk in Him, rooted and built up in Him and established in the faith, as you have been taught, abounding in it with thanksgiving. Col 2:6,7
…holding the mystery of the faith with a pure conscience. 1 Ti 3:9
Now the Spirit expressly says that in latter times some will depart from the faith, giving heed to deceiving spirits and doctrines of demons, 1 Ti 4:1
If you instruct the brethren in these things, you will be a good minister of Jesus Christ, nourished in the words of faith and of the good doctrine which you have carefully followed. 1 Ti 4:6