Unwonted

Be of comfort; / My father's of a better nature, sir, / Than he appears by speech: this is unwonted, / Which now came from him.

After the first flutter of conscious delight which his entrance had caused, she was able to talk to him cheerfully, and her spirits rose with the unwonted enjoyment.

And Rick with unwonted diffidence had accepted his exclusion. Now with the same diffidence he came, looking trim and loving and mysteriously humble.

...And ocean salinity, of course, represented only the merest sliver of my ignorance. I didn't know what a proton was, didn't know a quark from a quasar, didn't know how geologists could look at a layer of rock on a canyon wall and tell you how old it was, didn't know anything, really. I became gripped by a quiet, unwonted but insistent urge to know a little more about these matters and to understand above all how people figured them out.

[...] enjoying in their quiet way the unwonted atmosphere of youth and happiness.

On the other hand, it was not so well known among them that Moses was always to be their ruler, and so it behooved those who rebelled against his authority to be punished in a miraculous and unwonted manner.