Proverbs 23:19-25

There is often a price to be paid in obtaining the truth of God, and we should be willing to pay the price, whatever it may be. Once having obtained the truth, we should not give it up.

The verse is not to be taken with such strict literalness that we would buy Bibles and Christian literature, but would not sell them under any circumstances. Buying the truth here means making great sacrifices to achieve the knowledge of divine principles. It may mean hostility from one's family, loss...