A retooled classic hitting bookstores this week will raise new questions for millions of Christians about the nature of sin, whether women can exert authority over men and what the word "booty" really means.

That book is the Bible.

On Wednesday, as many Christians begin observing Lent, American publishers will release new translations of two of the most widely read English language Bibles - the official Catholic version and the most popular evangelical version - that together have been printed more than 415 million times.

These are the first new translations of the New American Bible (Catholic version) and the New International Version (the one more popular with evangelicals) in decades, and are being introduced into a radically changed scripture marketplace.

As late as the 1950s, a few translations dominated English-speaking Christianity. Today there are dozens, and even more niche-marketed Bible study guides: for women, youths, cartoon lovers, golfers, people who only want to carry a thin volume. The new NIV alone has 33 different study guides coming out by this summer.

Far from relying on one book and a pastor, American Christians today can sit in the pew during a Sunday sermon and use their phone to flip through 50 interpretations of any particular passage of the New or Old Testatment and compare wording.

With the Bible business growing more crowded, publishers want to stay fresh with the way young people use words and with the latest scholarly research.

Although most of the changes in the new versions are subtle language tweaks meant to make it more readable, the books reflect stepped-up debate about how to understand Christianity's holy scriptures.

The most controversial part of the new NIV is its removal of some of the gender-neutral language that publishers inserted in a version that was half-released in 2005, but then quashed because of criticism by conservatives. The new version, for example, replaces in Genesis God's call to make "human beings in our image" with "mankind."

The new NIV also tries to make wording less rigid in certain places, said Doug Moo, chairman of the 15-member translation committee. For example, it replaces the ban on women "exercising" authority over men in church from the 1984 version - the last official NIV - with the potentially softer "assuming" of authority.

"Whether that referred to all forms of authority over men in church or only certain forms in certain contexts is up to the individual interpreter to decide," read translation notes for the new version.

It replaces multiple uses of "sinful nature" with "flesh," which Moo said is meant to leave to the reader the question of whether sin is a core human element or one of many outside forces to which we yield.