Craft a musical piece that integrates the provided melodic theme and the corresponding alphabetical pattern.
X:1
L:1/8
Q:1/2=60
M:4/4
K:G
['gbag gfed cBAG FE E2 gbag f2', 'D2 Bd Td2 ec Tc2 Ac Tc2']  
X:1
L:1/8
Q:1/2=60
M:4/4
K:G
 gbag gfed | cBAG FE E2 | gbag f2 ed | cBAG D2 D2 :: Bd Td2 ec Tc2 | Ac Tc2 dB TB2 | 
 GB TB2 cA TAB/c/ | dBcA G2 G2 :|  