"And Jacob kissed Rachel" (Genesis 29:11). Every kiss is for frivolity except for three: the kiss of high office — "And Samuel took the flask of oil… and kissed him" (1 Samuel 10); the kiss of reunion after separation — "And he went and met him at the mountain of God and kissed him" (Exodus 4:27); and the kiss of parting — "And Orpah kissed her mother-in-law" (Ruth 1:14). Rabbi Tanhuma said: Also the kiss of kinship — "And Jacob kissed Rachel," for she was his kinswoman. "And he lifted up his voice and wept." Why did he weep? He said: When Eliezer went to bring Rebecca, what is written of him? "And the servant took ten camels" (Genesis 24:10), and I have not even one nose-ring or one bracelet.
Three Kinds of Worthy Kisses and Why Jacob Wept
Yalkut Shimoni on Torah 124:4
(בראשית כט יא) וַיִּשַּׁק יַעֲקֹב לְרָחֵל. כָּל נְשִׁיקָה לְתִפְלוּת, בַּר מִתְּלָתָא נְשִׁיקָה שֶׁל גְּדֻלָּה "וַיִּקַּח שְׁמוּאֵל אֶת פַּךְ הַשֶּׁמֶן וְגוֹ' וַיִּשָּׁקֵהוּ", נְשִׁיקָה שֶׁל פְּרָקִים, (שמות ד, כז) "וַיֵּלֶךְ וַיִּפְגְּשֵׁהוּ בְּהַר הָאֱלֹהִים וַיִּשַּׁק לוֹ", נְשִׁיקָה שֶׁל פְּרִישׁוּת (רות א, יד) "וַתִּשַּׁק עָרְפָּה לַחֲמוֹתָהּ" רַבִּי תַּנְחוּמָא אָמַר, אַף נְשִׁיקָה שֶׁל קְרֵבוּת וַיִּשַּׁק יַעֲקֹב לְרָחֵל שֶׁהָיְתָה קְרוֹבָתוֹ. וַיִּשָּׂא אֶת קֹלוֹ וַיֵּבְךְּ. לָמָּה בָּכָה, אָמַר, אֱלִיעֶזֶר בְּשָׁעָה שֶׁהָלַךְ לְהָבִיא אֶת רִבְקָה מַה כְּתִיב בֵּיהּ (בראשית כד, י) "וַיִּקַּח הָעֶבֶד עֲשָׂרָה גְמַלִּים", וַאֲנִי לֹא נֶזֶם אֶחָד וְלֹא צָמִיד אֶחָד.