Before we revisit the topic of abortion let me interject, and remind you and myself why we should care in the first place. Why is it worth our time and energies to speak on a topic that is so volitile?
Let me begin at the beginning:
Let’s assume (and save the ontological arguments for another day), there is a God.
Assuming there is a God, ontologically speaking there can be only one; the culmination of all things good, the ultimate, the embodiment of all things perfect–i.e. the meaning of the word “God”.
So, if there is a God, who is perfect and only one, who is he?
Three religions talk about one God, Judaism, Christianity, and Islam. I don’t have time in this post to discuss my philosophical conclusions regarding the God of Islam and Judaism (Judaism meaning the post-Jesus religion that denies Jesus of Nazareth as the Messiah), so I’ll just say this: The God of Christianity, described from Genesis through Revelation is the only God that embodies “perfection” philosophically (justice, love, mercy, creativity, truth…etc) in my opinion.
So, assuming this one God is in fact the Christian God, incarnated in Jesus Christ, then Dietrich Bonhoeffer’s ethical theory seems the most logical as it most adheres to Jesus’ own ethical code, i.e., obedience to the word of God and full reliance on his relationship with the Father for specific directions, with the logical assumptions that God is good, just and loving. Jesus put it plainly:

Then they said to him, “What must we do, to be doing the works of God?” Jesus answered them, “This is the work of God, that you believe in him whom he has sent.” John 6:28-29 ESV

Our Ethics begin with faith, they begin with Christ and it is from him that we are pushed into action.

Whoever wishes to take up the problem of a Christian ethic must be confronted at once with a demand which is quite without parallel. He must from the outset discard as irrelevant the two questions which alone compel him to concern himself with the problem of ethics, “How can I be good?” and “How can I do good?” and instead of these he must ask the utterly and totally different question “What is the will of God.” This requirement is so immensely far-reaching because it presupposes a decision with regard to the ultimate reality; it presupposes a decision of faith. If the ethical problem presents itself essentially in the form of enquiries about one’s own being good and doing good, this means that it has already been decided that it is the self and the world which are the ultimate reality. The aim of all ethical reflection is, then, that i myself shall be good and that the world shall become good through my action. But the problem of ethics at once assumes a new aspect if it becomes apparent that these realities, myself and the world, themselves lie embedded in a quite different reality, namely, the reality of God, the Creator, Reconciler, Redeemer[…] For without God what meaning could there be in a goodness of man and goodness of the world?
Dietrich Bonhoeffer, Ethics

So, if as Christians, our Ethics must look different then the Ethics or moral code of the world, namely that they must rely on faith and ultimately continue to ask the question, “What is the will of God?”, what does this mean practically?

It means you should care, dear Christian brothers and sisters. It means that you cannot simply get by with the world’s standard of being a “good person”, because you know there is no such thing. It means you must be intimately acquainted with this God who is the ultimate good, this God who made himself flesh so we could know him, so that he could step into our crooked reality that tries to push him out of it, this God who died because there are no “good people”–not by the standard of goodness that he is and requires–this God who took our place in punishment so we could know him and be restored to what we were meant to be. And because he died, and rose and gave us new life, we can’t go on living as if reality excludes him, we have to care about what he cares about, and act and speak by his leading.
Jesus said, “follow me,” and that means much more then we often like to think it means.

To follow means to follow, not to lead. To point not to our own superior moral character but to the dimly seen figure out there that we are stumbling after.
In fact to follow means to understand with awful clarity that we have no superior moral character in the first place[…]because the voice that we hear over our shoulders never says, “First be sure that your motives are pure and selfless and then follow me.” If it did, then we could none of us follow. So when later on the voice says, “Take up your cross and follow me,” at least part of what is meant by ‘cross’ is our realization that we are seldom any less then nine parts fake.
-Frederick Buechner, The Magnificent Defeat

This means when we enter in discussions regarding abortion (or any other issue of ethics) we must begin and end with the cross. We must remember, regardless of the passion and anger that rises from discussion, that this discussion is worth having because of love. God loves us, so much that he suffered and died on our behalf, and because of that love he wants us to walk in deeds that are good and, yes, ethical. I love those who disagree with me on this topic, and because I love them, it’s worth the heated debate. Most of all, I love the women who are caught in the deception that abortion is an easy way out, and I want desperately for them to know the truth. I love them, and greatest of all, God loves them; and because I am a part of his body through Christ, I have an obligation to speak his word. And if you claim him, you do too.

You can’t go on pretending not to see as children who God loves and values are being torn apart because someone else decided they aren’t valuable; and you can’t turn a deaf ear as women plea for help and are answered deceptively with the empty promise that sacrificing the life of their child will give them peace, or freedom, or success.

If we claim that we do indeed follow him, then let’s let him lead us, no matter how uncomfortable it may be. Let’s truly follow this God who became man and showed us every person is valuable, not because of something they have to offer, but because he loved them enough to die for them. Let’s stop pretending that reality excludes him, and instead embrace the reality that he is God and live in a way that embodies that. Let’s care deeply about what he cares about, and love people truly, even if that means speaking unpopular words, because he loves them and desires that they know him as we do.

Sources Consulted
Ethics By Dietrich Bonhoeffer I highly recommend this book to everyone
A Short History if Ethics by Alasdair MacIntyre
Ethics for a Brave New World By John S. Feinberg and Paul D. Feinberg