In the name of the father, the son and the holy ghost is translated as following:
In nomine patris, filii et spiritus sancti
my question: why ‘patris’. The termination of the genitive singular that belongs to ‘pater’ is ‘-i’, and why not ‘spiriti sancti’?
The gentive -i ending is only for second declension nouns. Pater is third declension (genitive -is) and spiritus is fourth declension (genitive -us).
Ah ok 
, I haven’t learned the last three declensions yet. Thanks for your information .
Never a problem. 