If you wish to be thankful, get a heart deeply humbled with the sense of your own vileness. A broken heart is the best pipe to sound forth God's praise. He who studies his sins, wonders that he has anything, and that God should shine on such a dunghill: "I was once a blasphemer and a persecutor and a violent man—but I was shown mercy!" (1 Timothy 1:13). How thankful Paul was! How he trumpeted forth free grace!
A proud man will never be thankful. He looks on all his mercies as either of his own procuring or deserving. If he has an estate, this he got by his wits and industry; not considering that scripture, "Always remember that it is the Lord your God who gives you power to become rich" (Dt. 8:18). Pride stops the current of gratitude. O Christian, think of your unworthiness; see yourself as the least of saints, and the chief of sinners—and then you will be thankful.