'Once' in the Bible

they only kept hearing, “He who used to persecute us is now preaching the [good news of the] faith which he once was trying to destroy.”

Brothers and sisters, I speak in terms of human relations: even though a last will and testament is just a human covenant, yet when it has been signed and made legally binding, no one sets it aside or adds to it [modifying it in some way].

Now, however, since you have come to know [the true] God [through personal experience], or rather to be known by God, how is it that you are turning back again to the weak and worthless elemental principles [of religions and philosophies], to which you want to be enslaved all over again?

What then has become of that sense of blessing and the joy that you once had [from your salvation and your relationship with Christ]? For I testify of you that, if possible, you would have torn out your own eyes and given them to me [to replace mine].

It was for this freedom that Christ set us free [completely liberating us]; therefore keep standing firm and do not be subject again to a yoke of slavery [which you once removed].

Once more I solemnly affirm to every man who receives circumcision [as a supposed requirement of salvation], that he is under obligation and required to keep the whole Law.