Solemnly

But Judah replied, “The man solemnly warned us, ‘You will not see my face again unless your brother is with you.’

But Moses said to the LORD, “The people cannot come up Mount Sinai, for You solemnly warned us, ‘Put a boundary around the mountain and set it apart as holy.’”

…he said to them, “Take to heart all the words I have solemnly declared to you this day, so that you may command your children to carefully follow all the words of this law.

Now listen to their voice; but you must solemnly warn them and show them the manner of the king who will reign over them.”

…and no one should ever violate or exploit his brother in this regard, because the Lord will avenge all such acts, as we have already told you and solemnly warned you.

I solemnly charge you before God and Christ Jesus and the elect angels to maintain these principles without bias, and to do nothing out of partiality.