Volunteer expenses, including mileage, are deductible as a charitable contribution. Enter as a cash contribution. Mileage, including mileage from your home to and from the first church, is deductible at the 14 cents/mile charity rate; not the 58 cent business rate.
Charitable deductions are only an itemized deduction. Until all you itemized deduction exceed your standard deduction ($12,200 single, $24,400 Married filing Jointly) you will see no benefit. Itemized deductions are instead of the standard deduction, not in addition to it.
If you are a paid music director, see the other replies.
