Performing One’s Duty Without Attachment
One who performs his duty without attachment, surrendering the results unto the Supreme Lord, is unaffected by sinful action, as the lotus leaf is untouched by water.
Primary Factor For Married Couples
They (The married couples) should know that bodily relations between the husband and wife is secondary ; primary factor is that both should help one another in the matter of advancement of Krishna consciousness.
Husband As The Instructor
Regarding your question about the husband becoming the spiritual master of the wife, anyone who can give instruction in spiritual life is treated as spiritual master. There are two kinds of spiritual master, initiator and instructor. So the husband can help the wife as instructor.
A.C. Bhaktivedanta Swami Prabhupada
In his letter to Himavati, 24th January, 1969.
Guidance
Spiritual master is representative of God. Similarly, king is also representative of God. The father is also representative of God. These are the statements of the sastras. Because they will guide. The king will guide. The spiritual master will guide. The father will guide. What is that guidance? That guidance is how one can become Krishna Conscious by education, by culture.