"Freely you have received, freely give."
".... And whosoever will, let him take the
water of life freely." (Rev 22:17)
John 3:16 says that God loved the world so much
that He gave His Son.
It does not say that He sold His Son.
God never intended for His Word, or the study of
His Word, to be sold.
He wants it to be available to "whosoever will."
can do no less.