I don't understand your position. You seem to be speaking on God's behalf.
There are literally millions of books which aren't in the Bible for one reason or another. Choosing among the non-canonical seems a bit of hubris. (I'd add On Civil Disobedience by Thoreau and Letter from a Birmingham Jail by King. But who asked me, right?)
The Epistle of Barnabas's chief thrust is that the Jews misunderstood their own sacred writing. Are you just going to pick and choose among the points of this letter? In for a penny, in for a pound.
As has been mentioned before, the only mention of causing the death of a fetus in the OT treats it as a property crime.
Anyone can have their own judgment on the issue, but I don't see how Christians can substitute their own judgment for what they claim is Divine Revelation.