"Many people ask for God's blessing before they partake of a meal, but the Jews were instructed also to give thanks after the meal was eaten. 'When you have eaten and are satisfied, praise the Lord your God for the good land he has given you' (Deuteronomy 8:10). Why? The answer is in Deuteronomy 6:11-12: 'Then when you eat and are satisfied, be careful that you do not forget the Lord.' When our blessings are more meaningful to us than the God who gave them, we've taken the first step toward idolatry. It delights the heart of God when His children are thankful for the Giver, and not just the gifts."- Warren W. Wiersbe
Source: Wiersbe, Warren W. Bless You: Receiving and Sharing the Blessings of the Lord. Grand Rapids: Zondervan, 2008. 16. Print.