Midrash for Taanit 7:16
ואיכא דאמרי לימא
She further made another thoughtless request. She said before Him,: O God, Set me as a seal upon thy heart,- as a seal upon thine arm.<span class="x" onmousemove="('comment',' Cant. VIII, 6.');"><sup>18</sup></span> Thereupon the Holy One, blessed be He, replied to her: My daughter, thou askest for something which at times can be seen and at other times cannot be seen. I, however, will make of thee something which can be seen at all times, as it is said, Behold I have graven thee upon the palms of My hands.<span class="x" onmousemove="('comment',' Isa. XLIX, 16. A seal on the heart and arm is not always visible. Hence the reply of God.');"><sup>19</sup></span> WE PRAY FOR RAIN ONLY etc. [The scholars] were of the opinion that 'praying' and 'making mention' are one and the same thing. Who is the authority for this? -Raba replied: It is R'Joshua, who said, [We begin to make mention of rain] from the time when the Lulab is discarded -<span class="x" onmousemove="('comment',' Supra 2b. After the seventh day which is close to the rainy season.');"><sup>20</sup></span> Abaye said to him: You can even say, that it is R'Eliezer; 'praying', however, is one thing and 'making mention' is another. Others have the reading: