A few weeks ago I had a Sunday off at my church (our students were leading worship that morning) and so I accepted an invitation to lead at a church whose worship leader needed a sub since he was going to be the one preaching that morning. I had a great time, and really enjoyed meeting the congregation and musicians there.
After our pre-service rehearsal, one of the singers said to me “Sam is going to be so happy that you’re doing so many hymns!” I laughed and said “You guys have a Sam too?”. It’s true. Every church has him. Maybe his name isn’t Sam, but you know who I’m talking about.
He’s that guy who’s very comfortable letting you know whether or not you/your songs/your number of hymns/your choice of the wording of “Be Thou My Vision”/your choice of whether or not to wear a tie has been met with his approval or disapproval. You see him coming and you’re tempted to run the other way.
How do you handle “that guy”?
Don’t let him get under your skin. Don’t let him intimidate you. Don’t let him approach you in those sensitive minutes before or after the service and throw you off your game.
Instead, give him what he wants: an equally strong opinion back, with a smile and a laugh. “That guy” has a strong enough personality to confront you with his opinions, so you have to channel a strong enough personality to hand it right back to him.
Don’t be a jerk, but do be firm. Find him amusing. Love him. Call him by his first name. Give him a firm handshake. If you’re in the mood, listen to what he has to say, thank him, and tell him what you think. If you’re not in the mood, say hi to him and tell him it’s not a great time. He’ll appreciate your strength and he’ll back off.
Whatever you do, don’t let that guy get under your skin. He’s just a person who wants to be liked. Like him, be firm, and be comfortable being strong.
Worthily Magnify 
What about when “that guy” is the pastor? You do everything he has asked and jump through his hoops every week and still feel like he’s just waiting to criticize any and everything.
If the last (almost) 9 years with my pastor have taught me anything, it’s that when you tell the pastor in advance what you’re plans are, and he either explicitly says “OK” or implicitly says “OK” by not saying “no”, then he has no excuse to criticize you.
And if my upbringing as a preacher’s kid taught me anything, it’s that pastors are real people who can kind of be jerks sometimes, and who shouldn’t be treated as if they’re precious. Thankfully, my pastor doesn’t expect to be. Tell him, to his face, that his criticism of you is driving you insane. Let him hear how frustrated you are. Communicate your heart to him. Be comfortable pushing back as much as you can. It’s good for him and it’s good for you. Always respect him. And don’t feel guilty expecting his respect in return.