If the Gospel wasn't clear and we couldn't actually know what it was...
If the Gospel was not clear and we could not know it was... then Paul was so very wrong in writing as he did to the churches of Galatia. If theological precision and accuracy concerning the nature of the Gospel is not particularly important for unity amongst "brothers", then it would follow that the following imaginary letter to Paul would needed to have been written (found at Dr. James White's web site) to correct his extreme narrow mindedness:
In reviewing your letter to the churches of Galatia, we, the modern men of the 21st century, have come to the conclusion that you truly missed the point in your very pointed and, may we say, unloving comments regarding the faithful brothers with whom you had but a minor theological difference. We are in particular offended that you would identify men who clearly confess faith in Christ and who have risked their lives for their faith "false brethren." Who are you to make such a harsh judgment, in light of their many evidences of faith? These men are Christians, and to call them false brethren is a serious sin! You are bearing false witness against them! And to dare to read the intentions of their hearts so as to say they were "sneaking" into the fellowship is simply beyond the pale. You should be ashamed of yourself! All you disagree on is a minor point of theology! They believe in Christ! They believe in His resurrection! They simply believe one should be circumcised so as to be a part of the covenant people of God! How narrow of you to exclude them from the fellowship of faith simply on the basis of such a minor thing as this! Why won't you focus upon the areas of agreement you have? Why focus only upon differences, the negatives? Don't you realize you will never win people to your views if you continue to act in this fashion? We seriously request that you apologize to the faithful brothers you anathematized in your ill-advised letter to the churches of Galatia. By this, true peace and unity might be achieved!
Selah (stop, think and meditate) - with Scripture alone as our firm foundation we affirm that justification is by grace alone, through faith alone, because of Christ alone, all to the glory of God alone. - JS