This quotation is an effective summary of the Christian imperialism that affected Nigeria and many other countries, both in Africa and around the world.
Because of this imperialism, the Ibo people of Nigeria were almost forced to abandon many of their cultural and religious traditions in favor of Christian traditions. Those Christian traditions are represented by the Bible in this quotation; the land represents Ibo way of life, their "home," that had to be abandoned. So, this quotation works on both a literal and figurative level. Yes, the Ibo people lost much their land and gained a Bible, but they also lost many of their cultural traditions and their identity in exchange for Christianity.
I do not see a question, but I wonder if you are looking for an explanation of this quote.
This quote is talking about how colonization affects the societies that are colonized. It is also commenting on the motives of the colonizers.
One stated goal of European and American colonization has been to spread the "true" religion to others. You would think that this would mean that they would also act in Christian ways. This quote is saying that they did not act in Christian ways. Instead, the took everything they could. The natives ended up with Christianity, but the colonizers took everything of value.
In Hawaii there was a similar saying that the missionaries found the islands in "darkness" and left them "lighter" because they stole everything that wasn't nailed down.