'Simple' in the Bible

Since otherwise, if thou blessest with the spirit, how shall he who fills the place of the simple Christian say Amen, at thy giving of thanks, since he does not know what thou sayest?

If therefore the whole assembly come together in one place, and all speak with tongues, and simple persons enter in, or unbelievers, will not they say ye are mad?

But if all prophesy, and some unbeliever or simple person come in, he is convicted of all, he is judged of all;