I offer my heartfelt congratulations and best wishes to you both.
Please accept our heartfelt gratitude for your financial support over the last sixteen months.
A handwritten note will usually suffice for a heartfelt thank you.
My heartfelt sympathy is extended to the family circle.
Whether you write a rhyming prayer, a prayer dotted with lots of uses of "thee" and "thou", or a prayer that reads like you're talking to your best friend, with a little brainstorming you can write your own heartfelt Christmas prayer.