I was raised Catholic and there's no way I would practice it for anyone, for any reason. Generally speaking, I'd rather vomit than sit through a mass. I could not conceive of a reason, at this point in my life, that I would ever stop practicing the Dhamma.
That being said, I couldn't agree more with Goofaholix about it being a tolerance issue vs a religious issue. You might be interested to check out books by John Gottman, a psychology who has done research on what factors make up happy marriages (as opposed to most people in the marriage counseling field who have been working on assumptions). See his book, The Seven Principles for Making Marriage Work. In it, he talks about "gridlock issues," perpetual problems like differences in religion, having/not having children, etc. where there is unlikely to be any compromise. The strategy is to move from gridlock to dialogue, and rather than resolve the issue, to make peace with the issue (i.e. develop acceptance, flexibility, finding common ground).
In many relationships, I have found the "common ground" approach to be useful. On some level, Buddhism is not as different from other religions as we may think. If we heed the message of the Simile of the Raft, any religion is just a means to get across to the other side. Once there, we set down the raft and move on. If you look at the work of Christian mystics, you will find that you are in very familiar territory. The only thing that changes is the vocabulary. The Cloud of Unknowing was written by an anonymous Christian mystic, and if you change the word "God" to "Ultimate reality" or Emptiness, it sounds like a Buddhist monk wrote it (albeit God is a little more personified version). St. Teresa of Avila, St. John of the Cross, Meister Eckhart are other examples from history. Eckhart Tolle regularly uses examples from Jesus to illustrate points that seem to come straight out of the Dhamma.
Contemporary writers have addressed this too. Thich Nhat Hanh wrote Living Buddha, Living Christ
and Going Home: Jesus and Buddha as Brothers
. A very easy book for someone to sink their teeth into in this genre is Marcus Borg's Jesus and Buddha: The Parallel Sayings
. Buddhadasa Bhikkhu wrote that “those who have penetrated to the highest understanding will feel that the thing called ‘religion’ doesn't exist after all. There is no Buddhism; there is no Christianity; there is no Islam. How can they be the same or in conflict when they don't even exist?" ("No Religion," 1967. http://www.what-buddha-taught.net/Books ... ligion.htm
I used to feel irritated whenever people spoke about God, Jesus, etc., wishing they would just shut the hell up. Now when I hear them speak, I think of the Buddhist equivalent of what they are saying and I actually appreciate them for it. For example, I have a relative who often says "It's in the Lord's hands." I see that as her accepting the inevitable, not trying to control the uncontrollable, which I choose to call "equanimity." Angels or devas, saints or bodhisattvas & arhants. You say tomato, I say to-mah-to. Finding middle ground and equivalent terms has made family occasions a hell of a lot (pardon the pun) more enjoyable for me, which in turn allows me to better practice compassion and kindness. There are no losers in that game.
That being said, Christians can be a little adamant about joining Team Jesus, declaring strict allegiance, attending services, and tithing. It has survived as well as it has because of its pernicious memes. It actively encourages inflexibility in that regard. So all the more reason to have patience and compassion for those who buy into it wholeheartedly. Either you wife will be moved, sooner or later, by your honesty and sincere efforts to find a middle ground and appreciate what is so important to her. If not, then she is struggling horribly with choosing between the religion she holds dear and the man she has chosen to spend her life with (and you know how serious those Christians are about that whole "marriage" thing.) So that must be a difficult conflict for her to live with. Check out Shantideva's chapter on Patience (especially Pema Chodron's commentary in No Time To Lose
) Our greatest "adversaries" can be our greatest teachers, if we choose to recognize them as such. There is actually something to be gained from difficulties like this.
P.S. Another family member of mine told me she's reading the Jesus Sutras in her bible study group. I kid you not. It's the writings of an 11th century Christian missionary into China, who had to express Christian ideas in a Taoist/Buddhist framework. The author states that "fourteen hundred years ago, the Jesus Sutras had already created a synthesis of Tao, Christ, and Buddha."http://www.amazon.com/Jesus-Sutras-Redi ... 0345434242