'Nature' in the Bible
Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others.
For He is our peace--He who has made Jews and Gentiles one, and in His own human nature has broken down the hostile dividing wall,
for their [moral] understanding is darkened and their reasoning is clouded; [they are] alienated and self-banished from the life of God [with no share in it; this is] because of the [willful] ignorance and spiritual blindness that is [deep-seated] within them, because of the hardness and insensitivity of their heart.
Regarding your former way of life, you were taught to strip off your old nature, which is being ruined by its deceptive desires,
and to clothe yourselves with the new nature, which was created according to God's image in righteousness and true holiness.