The best time would for the 2nd service which starts at 12 noon. There will be a line for visitors so you should arrive around 11;30 @ the latest. From 39th street you can catch the 2, 3, or A train & exit at 135th st. The church is located on 138th St between Lenox & Adam Clayton Powell Blvd.
Email the church from the website and explain why you want to attend. They will likely make a reservation for you. Don't wait too long. Take the subway. Eat at Sylvia's afterwards and notice the formal, colorful Sunday dress of the neighborhood.
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