Don't rebuke an older man, but exhort him as a father; the younger men as brothers;
The younger men as brethren ...  A glimpse of the apostolic conception of the Christian community shines in these verses.  Various Christians are as fathers, mothers, sisters and brothers, as determined by their age and sex.  In fact the church itself has been described as a divine extension of the family, the family being, in every way, just as sacred and divine as the church.  In fact, the family antedates either the church or any state; but in the prevalence of sin and corruption, it often happens that the church family preserves more of the genuine family love and mutual concern than may be found in some families.  Although the fact does not seem to be in Paul's thought here, this correct evaluation of all church members as brothers, sisters, etc., is a great deterrent to immorality and other sinful practices.