In Hebrew, the word “train up” is usually translated as “dedicate.” Thus, it may indicate that the child is to be devoted to God (though NOT as Hannah did in 1 Sam.1:11) or it may simply indicate that the child is to be prepared for the responsibility he or she will know as an adult. However, since we are talking about family and marriage, the word “train up” is not only applicable to the child but also to both husband and wife.
The account of how a nation that was totally committed to God – in one generation – walked away from God and became an idolatrous nation. There’s a parallel to where we are today.