A pastor's wife's duties are to be a help-meet and support her husband and volunteer in tasks in which she is specifically gifted. No other duties are defined for a pastor's wife.
A pastor's wife has the role, as any wife, to help a husband in his needs. She is to nurture and support a husband and family. Wives are called to submit, meaning yield and follow, a husband without reproach or resentment. A wife is called to pray for and with her husband.
A pastor has specific duties to perform and a pastor's wife should support these duties. A pastor is to lead his home, a pastor's wife comes along side him in this task. A pastor is to be hospitable to others, his wife is welcoming. A pastor aspires to a life of integrity, a wife encourages and assists him.
A pastor's wife is involved in her church but not expected to play piano, counsel, teach bible study, sing in choir and do everything. A pastor's wife is to use her specific God-given strengths in the church. If she is able to teach, she fills that need. If her gift is hospitality, she helps with the welcoming committee. If a pastor's wife cannot sing or play piano, she is not expected to.