'Solemn' in the Bible

He attacks his friends; he breaks his solemn promises to them.

They have seen Your [solemn] procession, O God,The procession of my God, my King, into the sanctuary [in holiness].

Blow up the trumpet in the new moon, in the time appointed, on our solemn feast day.

Upon an instrument of ten strings, and upon the psaltery; upon the harp with a solemn sound.

So he made a solemn vow that he would make them die in the desert,