{But I buffet my body} (alla hup(9370)iaz(9320)mou to s(936d)a). In
Aristophanes, Aristotle, Plutarch, from hup(9370)ion, and that from
hupo and ops (in papyri), the part of the face under the
eyes, a blow in the face, to beat black and blue. In N.T. only
here and  Lu 18:5  which see. Paul does not, like the Gnostics,
consider his sarx or his s(936d)a sinful and evil. But "it is
like the horses in a chariot race, which must be kept well in
hand by whip and rein if the prize is to be secured" (Robertson
and Plummer). The boxers often used boxing gloves (cestus, of
ox-hide bands) which gave telling blows. Paul was not willing for
his body to be his master. He found good as the outcome of this
self-discipline ( 2Co 12:7  Ro 8:13  Col 2:23  3:5 ). {And bring
it into bondage} (kai doulag(9367)(935c)). Late compound verb from
doulag(9367)os, in Diodorus Siculus, Epictetus and substantive in
papyri. It is the metaphor of the victor leading the vanquished
as captive and slave. {Lest by any means} (m(8820)p(9373)). Common
conjunction for negative purpose with subjunctive as here
(gen(936d)ai, second aorist middle). {After that I have preached to
others} (allois k(8872)(9678)as). First aorist active participle of
k(8872)uss(935c) (see on 气:23|), common verb to preach, from word
k(8872)ux (herald) and that is probably the idea here. A k(8872)ux at
the games announced the rules of the game and called out the
competitors. So Paul is not merely a herald, but a competitor
also. {I myself should be rejected} (autos adokimos gen(936d)ai).
Literally, "I myself should become rejected." Adokimos is an
old adjective used of metals, coin, soil ( Heb 6:8 ) and in a
moral sense only by Paul in N.T. ( 1Co 9:27  2Co 13:5-7  Ro 1:28  Tit 1:16  2Ti 3:8 ). It means not standing the test (dokimos
from dokimaz(935c)). Paul means rejected for the {prize}, not for
the entrance to the race. He will fail to win if he breaks the
rules of the game ( Mt 7:22f. ). What is the prize before Paul?
Is it that {reward} (misthos) of which he spoke in verse  18 ,
his glorying of preaching a free gospel? So Edwards argues. Most
writers take Paul to refer to the possibility of his rejection in
his personal salvation at the end of the race. He does not claim
absolute perfection ( Php 3:12 ) and so he presses on. At the end
he has serene confidence ( 2Ti 4:7 ) with the race run and won.
It is a humbling thought for us all to see this wholesome fear
instead of smug complacency in this greatest of all heralds of
Christ.