This morning I was looking at MN 97, the Dhanañjani Sutta, which concerns an unheedful householder:
The householder, Dhanañjani, has apparently fallen into such negligence due to the pressures of daily life. Later, when he falls ill, Ven. Sariputta pays him a visit and teaches him the brahma viharas.Relying on the king, he plunders brahmans & householders. Relying on the brahmans & householders, he plunders the king. His wife — a woman of faith, fetched from a family with faith — has died. He has fetched another wife — a woman of no faith — from a family with no faith.
However, the Buddha then rebukes Ven. Sariputta, saying that this teaching only led to Dhanañjani's being born into the "inferior brahma world".
My question is: what should Sariputta have done instead? Dhanañjani's background and capabilities did not seem to have made him a good candidate for any higher teaching. He was evidently not ripe for liberation. Generally the Buddha provides those teachings which are suitable for his audience. Although there was surely "more to be done", there was no time left to do it, and the student was in grave danger of falling into a lower realm. So why was Sariputta rebuked?
More generally, if the brahma viharas are pointless, why are they given such extended treatment in the Visuddhimagga, for example? Why practice them at all?
On a peripheral note, what is meant here by "a family with no faith"?