Al HaNisim Prayer — You performed a miracle and a wonder for them, and we shall give thanks to Your great Name.
Grace After Meals — We thank You, Hashem...because You have given to our forefather as a heritage a desirable, good and spacious land...
HaKol Yoducha — All will thank You and all will praise You...
Hallel Prayer — For to You it is fitting to give thanks, and unto Your Name it is proper to sing praises...
Ki L’Cha Tov L’Hodot — It is good to give thanks to You and pleasant to sing praises to Your name...
Mechilta 20:20 — Be not like those who honor their gods in prosperity and curse them in adversity. In pleasure or pain, give thanks!
Midrash Schochar Tov Psalms 95 — Great is the power of a thank you, and so Jonah says, \'And I, in a voice of thanks, will sacrifice to you.\'
Numbers Rabbah 10:5 — Abraham built an altar in thankfulness for the good tidings.
Passover Haggadah — Therefore, we are bound to thank, praise, laud, glorify, extol, honor, bless, exalt, and reverance Him Who performed for our fathers, and for us all these miracles.
Psalms 100:4 — Enter into His gates with thanksgiving, and into His courts with praise; give thanks unto Him, and bless His name.
Psalms 94:19 — When my cares are many...Your comforts delight my soul.
Shmuel Hanagid, Ben Mishlei #8 — Ingratitude to man is ingratitude to G-d.