Aloha @roklock,

Thank you for the Silent Night sheet music, btw.  I haven't played that one yet, but I do play Amazing Grace.  One thing that @Fiddlerman pointed out in one of his videos is to keep your fingers close to the strings while not playing them, but also to keep them on the strings in case you need to play the same note again.

Just before you play the B, you have to play the G.  Keep your 3rd finger down on the G and play the B with the 1st finger.  Because you already have your finger on the G, you can easily play it again.  In fact, you can keep it pressed down until you have to go to the E with the 1st finger on the D string.

You can do the same thing in Silent Night.  It's actually the same situation.  In measure 17, keep your 3rd finger down on the A string for the D, then play the F with the 1st finger on the E string, play the D again, then release the third finger so that the 1st finger can play the B.  You can leave your fingers on the strings so long as you don't have to play anything else on that string.  

I have only been playing since 1 September, so I an a rank beginner, but learning when I can rest my fingers on the strings is something I'm slowly picking up.  I hope this helps you out.  Of course, if this is confusing and hard to understand, maybe someone else here can explain it better.