'Nature' in the Bible

For this reason, God gave them up to vile passions. For their women changed the natural function into that which is against nature.

(for when Gentiles who don't have the law do by nature the things of the law, these, not having the law, are a law to themselves,

Won't the uncircumcision which is by nature, if it fulfills the law, judge you, who with the letter and circumcision are a transgressor of the law?

For if you were cut out of that which is by nature a wild olive tree, and were grafted contrary to nature into a good olive tree, how much more will these, which are the natural branches, be grafted into their own olive tree?