Rom_6:14  For sin shall not have dominion over you: for ye are not under the law, but under grace.

Rom_6:15  What then? shall we sin, because we are not under the law, but under grace? God forbid. (Our new man has no interest to sin. 1Jn 3:6)

We're under Christ now, instead of the law. It's a new way to relate with God.

Therefore,

1Co_6:12  All things are lawful unto me, but all things are not expedient: all things are lawful for me, but I will not be brought under the power(love not the world and it's things, but set affections above) of any.

Liberty to love, not lust:

1Co_9:20  And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law;

1Co_9:21  To them that are without law, as without law, (being not without law to God, but under the law to Christ,) that I might gain them that are without law.

Furthermore,

Gal_3:23  But before faith came, we were kept under the law, shut up unto the faith which should afterwards be revealed.

Gal_4:4  But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law, (Who is the end of the law, fulfilling the law of our approval)

Gal_4:5  To redeem(release) them that were under the law, that we might receive the adoption of sons.(instead)

Gal_5:18  But if ye be led of the Spirit, ye are not under the law.

Now then:(your message)

Rom_3:19  Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world (everyone before salvation) may become guilty before God.

Perhaps, your reason for replacing the sound words "under the law" in the pulpit was because you wanted to make it easier to understand. I mean, even though your word usage confuses the Bible usage- you may have did it for the sake of clarity. You wanted the people to still obey God despite having no obligation to serve under His law. (His mercy for sparing us from the afterlife is enough obligation, Paul says in Rom 12.)

You were likely thinking of these verses:

Rom_8:4  That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.

Rom_13:8  Owe no man any thing, but to love one another: for he that loveth another hath fulfilled the law.

Rom_13:10  Love worketh no ill to his neighbour: therefore love is the fulfilling of the law.

Both are true:

We see here that we end up fulfilling the law, without an obligation to it. Say that again: we’re not “under it”, but fulfill it anyway. (God likes faith, not the old man.)

(next, Rom 4:15)