Wealth promised for Christians in the OT?

The Lord will give you big harvests and make you successful in everything you do. You will be completely happy, so celebrate this festival in honour of the Lord your God. (Deuteronomy 16.13-15)

Reflect:  Scripture does not seem to rule out wealth for a Christian. Sometimes, as in the book of Job, it seems that wealth is a sign of God’s blessing. These verses today remind us that wealth should lead us to thanksgiving and worship. Jesus also seemed to be comfortable receiving invitations to eat with wealthy people he always left his hosts with a word of caution about their responsibility to the poor (see for example Luke 7.44).

Source: Worship & Wealth (23 October 2018) – Daily reflection – Bible Society

The writer applies the Old Testament passage directly to the Christian. This is a common mistake, but here it is more blatant than one usually encounters. The promises of the OT to Israel do not directly apply to the church.

The real difference between the old law and the new?

Romans 13 | Lumina

Whereas the Mosaic Law specified numerous situations in which the Israelites were to practice love, the Law of Christ contains comparatively few. The simple principle is enough. This is another excellent example of the essentially legal character of the Mosaic Law and the gracious character of Christ’s teachings. Jesus Christ gave us a model to follow in loving (John 13:34). Love promotes obedience.

This comment on verses 9-10 makes me wonder. There was much to emphasize about the heart and a sincere devotion in the OT. I need to think more on this.