THEME:   phrases containing letters T, H, I, N separated by other letters   
GOOD ONES:     Weakening, in a way, {& theme}   WEARING THIN   
Problem with pictures   REBUS [I thought the pictures had a problem]   
Occasions for shooting stars?   PHOTO OPS      
BTW:   The theme clue says the phrases are 
"literally" wearing the word thin.  Problem is phrases don't wear anything literally.  Maybe if  the modifier were "literarily" I could enjoy the rest of my day.      
How can it be that I remember that Certs contained RETSYN, which sounds like a portmanteau for pepsin and rennin?  Is advertising so profound?      
Bk. Before Phillippians   EPH [that's Ephesians, but what is amazing that in my teens I was taught a mnemonic for NT letters, and now I know why --- if it comes up in a Xword half a century later I'd know.  Retsyn and Ephesians in one day!          
RATING:    
 
 
Three grins = Loved it; Two grins = Enjoyed it; One grin = A bit bland for my taste; One teardrop = Not much fun