'Lack' in the Bible

Do not deprive each other [of marital rights], except perhaps by mutual consent for a time, so that you may devote yourselves [unhindered] to prayer, but come together again so that Satan will not tempt you [to sin] because of your lack of self-control.

while our more presentable parts do not require it. But God has combined the [whole] body, giving greater honor to that part which lacks it,

so that there would be no division or discord in the body [that is, lack of adaptation of the parts to each other], but that the parts may have the same concern for one another.