Gratitude is an indicator of holiness. If you read the writings of, or the Lives of, the great Saints, you'll see that they were suffused with a spirit of Gratitude. They were always thanking God for all they had, and taking notice of the smallest blessings.
Gratitude is also a remedy against Sin. It's the times when I'm most self-satisfied and taking things for granted that I end up being the most susceptible to temptation, and prone to become self-absorbed. Gratitude takes the attention away from yourself and puts it on the Giver. If you make the effort to practice gratitude, you will be come Holy. It's that simple.
I am grateful for many things today. Here are a few:
I'm grateful for my priesthood.
I'm grateful for the Grace by which Our Lord saved me.
I'm grateful for Our Lord's most holy gift of the Eucharist, and the unimaginable privilege he has given me as His priest, to make Him present on the Altar.
I'm grateful for my family: my mother, father, aunts, cousins, who have shown me so much love and support over the years.
I'm grateful for my friends: they have taught me so much, given me so much, shared with me so much, and mean so much to me.
I'm grateful for all the good things of this world: The beauty of Nature, the wonders of creation, red wine, champagne, Prime Angus steaks, Vienna Beef Chicago-style hot dogs, lobster, asparagus, good Scotch whisky, good Bourbon, cigars, and micro-brewed beers.
Great are the works of the Lord, to be treasured for all their delights!