The rectum contains more potentially harmful bacteria and viruses than the vagina. If anal penetration is practiced, some protection by condoms should be used and alternating penetration of the rectum and vagina avoided. The rectum is simply not designed for this kind of treatment and serious medical problems may result. Any sexual practice that feels forced on a mate violates the sense of safety and mutuality required for marital intimacy. That applies to oral sex, positions for intercourse, locations and situations for love making, or means of sexual stimulation.
Sex is intended for mutual pleasure and, like submission, requires giving by both husband and wife.
There are many times in marriage when one partner has to choose between his or her own pleasure or preferences and that of a spouse. If my desire for pleasure from a certain sexual activity takes precedence over my desire for Melissa's sense of being honored and protected within our relationship, I have violated her trust. It wouldn't matter how convincing my arguments or how persuasive my appeal, I would damage her. When there are things I would like to try, but she's not comfortable, it is important for me to let that be entirely up to her to initiate or request that experience. Meanwhile, I've given her the gift of my love and respect.