The Gideons are known to give out free New Testaments and Bibles in the USA and other countries around the world. The Bibles and New Testaments have the plan of salvation in them. They work in prisons and many other places.
Below are some online articles about the Gideons ministry in the prisons.
Ministry Behind Bars
How Does God’s Word Get Into Prisons? http://blog.gideons.org/2016/03/gideons-prison-ministry/
Reaching Prisoners With God’s Word
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