We know that in Judaism every halachicly mandated action or custom is imbued with profound meaning and symbolism.  Anything we are directed to do on a daily basis has even more significance.  If we are told to repeat that action three times a day, every day of the week, we can be sure that that action is of the utmost significance in our tradition.  This is, in fact, the exact situation we have with the prayer which is simply referred to as the “Ashrei”.  The Ashrei is recited twice during shacharit and once during mincha by every individual Jew, every day, whether he is davening alone or with a minyan.  Just what is it about this tefilla that makes it so special?
    The Gemara tells us that anyone who recites Ashrei three times a day is guaranteed to be a ben Olam Haba, someone who at the end of his days receives eternal reward in the World to Come. The Gemara explains that there are two reasons why this is the case. The first one has to do with the fact that if you list the first letter of each pasuk of ashrei individually, you find that you end up with the entire Hebrew alphabet, the Aleph Beis, listed in order from beginning to end.  The second reason mentioned is that within the body of Ashrei you find the famous pasuk of “Poteiach et yadecha umasbiah l’chol chai ratzon” which means “You open Your hand and satisfy the desire of every living thing.”
    The Maharsha explains that these two reasons are related.  The letters of the Aleph Beis that are contained within Ashrei symbolize Torah learning in general.  The Torah, which was given to us by way of the twenty-two letters of the Aleph Beis is the sustenance of our very souls. The pasuk of poteiach et yadecha found in Ashrei praises God for feeding every living creature, from the smallest bug to the largest animal, each according to its own needs. These two ideas, taken together, praise God for our complete and total sustenance. We praise Him for giving us the Torah, which is “food” for our souls and we praise Him for giving us bread which is food for our bodies.  In other words, the Ashrei helps us understand that Hashem gives us food so that we are able to learn Torah, so that we are able to do its Mitzvot, so that we can earn our reward in Olam Haba. 
    The Shulchan Aruch writes that one must concentrate on the pasuk of poteiach et yadecha as this is one of the primary focuses of the entire tefilla. If one did not concentrate, he should repeat that pasuk and finish the rest of the tefilla. If one remembers later, he may say the pasuk at the end of the tefilla and finish the rest of Ashrei.
    Our halachic authorities write that although Ashrei is a very important tefilla, when one comes late to mincha he should skip Ashrei and pray the Shemoneh Esrei with the congregation. One should be mindful that the main purpose of praying with a minyan is to pray Shemoneh Esrei together with it.
    Although the tefilla of Ashrei is primarily from Psalm 145 which begins “tehilla ledavid”, there are two verses added at the beginning and one verse added at the end. The two preliminary verses speak of sitting in God’s house in order to praise Him. These were instituted in order to fulfill the precept of waiting a short time before praising God. They also allude to saying Ashrei three times a day as the word ashrei is mentioned three times in these pesukim.  The pasuk of va’anachnu n’vareich which we say at the end of Ashrei and which translates as “We will bless God from this time and forever,” was added to provide an additional allusion to the eternal reward we receive for reciting Ashrei properly.
    In light of the above, and in the merit of our reciting Ashrei in the prescribed manner, may we all, im yirtza Hashem, share together in the great reward that is promised by Hakodesh Baruch Hu for fulfilling this precept.