'Simple minded' in the Bible

“Leave [behind] your foolishness [and the foolish] and live,And walk in the way of insight and understanding.”

You shall do this on the seventh [day] of the month for everyone who goes astray [and sins through error or ignorance] and for him who is naive; so shall you make atonement for the temple (house).

For such people do not serve our Lord Christ, but their own appetites and base desires. By smooth and flattering speech they deceive the hearts of the unsuspecting [the innocent and the naive].