1 Corinthians 6:12

All things are lawful unto me
That is, which are of an indifferent nature; otherwise everything is not lawful to be done:

but all things are not expedient;
when the doing of them destroys the peace, comfort, and edification of others; when it stumbles and grieves weak minds, and causes offence to them; see ( 1 Corinthians 10:23 )

all things are lawful for me;
which is repeated for the sake of saying the following words:

but I will not be brought under the power of any;
which would be very inexpedient, should any by the use of liberty in things indifferent, on the one hand, offend his brethren, and, on the other, bring himself into bondage to those very things he has the free use of; and therefore the apostle determines, that these shall not have the mastery over him, that he will use them, or not use them, at his pleasure. It is somewhat difficult to know what in particular he has respect unto, whether to what he had been treating of before, concerning going to law before unbelievers; and his sense be, that however lawful this might be in itself, yet it was not expedient, since it was exposing of themselves to ungodly persons, and a putting themselves under their power to judge and determine as they pleased; or whether to the use of meats forbidden under the law, or offered to idols; which though in themselves lawful to be eaten, every creature of God being good, and not to be refused and accounted common and unclean; yet it was not expedient to use this liberty, if a weak brother should be grieved, or a man himself become a slave to his appetite.