'Nature' in the Bible
But at that time, when you did not know [the true] God and were unacquainted with Him, you [Gentiles] were slaves to those [pagan] things which by [their very] nature were not and could not be gods at all.
But I say, walk habitually in the [Holy] Spirit [seek Him and be responsive to His guidance], and then you will certainly not carry out the desire of the sinful nature [which responds impulsively without regard for God and His precepts].
For the sinful nature has its desire which is opposed to the Spirit, and the [desire of the] Spirit opposes the sinful nature; for these [two, the sinful nature and the Spirit] are in direct opposition to each other [continually in conflict], so that you [as believers] do not [always] do whatever [good things] you want to do.
And those who belong to Christ Jesus have crucified the sinful nature together with its passions and appetites.
For the one who sows to his flesh [his sinful capacity, his worldliness, his disgraceful impulses] will reap from the flesh ruin and destruction, but the one who sows to the Spirit will from the Spirit reap eternal life.
For neither is circumcision anything [of any importance], nor uncircumcision, but [only] a new creation [which is the result of a new birth—a spiritual transformation—a new nature in Christ Jesus].