Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:C
['c c2 G G2 e faf', 'A e2 e2 c d2 e f3']  
X:1
L:1/8
M:6/8
K:C
 g | g2 e d2 c | c2 G G2 e | faf a2 f | (f3 e2) g | g2 e e2 c | c2 G G2 e | faf fed | c2 c c2 A :: 
{cd} | e2 e2 c | d2 e f3 | fed fed | e2 f g3 | gfe efg | abc' c'ba | gag fed | c2 c c2 :|  