Jude seems to take the right view of things, namely, that the proper way of meeting evils in the church is by dealing with the church itself—dealing with the truly faithful members of the church, and speaking to those who really are
Charles H. Spurgeonsanctified by God the Father, and preserved in Jesus Christ, and called—stirring them up to seek the highest degree of spiritual strength, and pleading for them that mercy and peace and love may be multiplied to them…The best protection against surrounding evil will be the cultivation of a right state of heart and life, a continual growth in grace and in the knowledge of the Lord.1
3 Beloved, although I was very eager to write to you about our common salvation, I found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints.