'Single' in the Bible

But I say to the unmarried and to the widows, [that as a practical matter] it is good if they remain [single and entirely devoted to the Lord] as I am.

(but even if she does leave him, let her remain single or else be reconciled to her husband) and that the husband should not leave his wife.

We must not indulge in [nor tolerate] sexual immorality, as some of them did, and twenty-three thousand [suddenly] fell [dead] in a single day!

If they all were a single organ, where would [the rest of] the body be?

But now [as things really are] there are many parts [different limbs and organs], but a single body.