Jews like to ask questions. Some say that Jews like to answer a question with another question. This is a strange thing to do.
Every Sabbath we end the morning prayers with a question, which is a verse from Tehillim, Psalms 106:
"Who can express the mighty acts of the L-RD, or make all His praise to be heard?"
This is also a strange thing to do, to finish the prayers with a question! Of course, this is a rhetorical question that is not meant to be answered. Nobody can express the mighty acts of the L-RD! It just cannot be done!
The verse itself seems to be redundant. The second part of the verse seems to repeat the first part of the verse. "Making all His praise to be heard" seems to be the same as "expressing the mighty acts of the L-RD."
The Maharal from Prague wrote a book about the Exodus, "Gevurot Hashem". In chapter 1 of Gevurot Hashem the Maharal explains that the verse is telling us two different ideas. The first part of the verse deals with quality, while the second part is talking about quality. "Who can express the mighty acts of the L-RD" in terms of the quality of his acts,” or make ALL His praise to be heard" in terms of quantity. Whether in terms of quality or in terms of quantity G-d's praises cannot be expressed!
Since this is so, the Maharal questions why we bother making a seder Passover night. While eating chicken soup with kneidlach is certainly a worthy pastime, the real purpose of the seder is to speak of the great miracles that G-d did for us as we left Egypt. But this is an impossible task! Who can express the mighty acts of the LORD, or make all His praise to be heard?
The Maharal answers that while we cannot possibly say all of G-d’s praises, we dare not be silent. This is called "Hakarat Hatov", recognizing and appreciating the good that someone has done for you. Gratitude. This is considered an important character trait that one should foster, and G-d forbid not to be a "Kefui Tovah", an ingrate. We say G-d's praises in order to show our appreciation and gratitude, even thought we know that our words cannot encompass all of the things that G-d is to be praised for.