סימן צ סעיף ט
אָסוּר לִתֵּן מַתָּנָה לַחֲבֵרוֹ, אֶלָּא דָּבָר שֶׁהוּא לְצֹרֶךְ שַׁבָּת. וְכֵן אָסוּר לִתֵּן מַשְׁכּוֹן לַחֲבֵרוֹ, אֶלָּא אִם כֵּן הוּא לְצֹרֶךְ מִצְוָה אוֹ לְצֹרֶךְ שַׁבָּת. וְלֹא יֹאמַר לוֹ הֵילָךְ מַשְׁכּוֹן, אֶלָּא נוֹתֵן סְתָם.
It is forbidden to give your friend a gift36Transactions are generally forbidden on Shabbos and Yom Tov, lest a person come to write. unless he has a need for it on Shabbos.37Or for any mitzvah purpose. [Bais Yosef 527] It is preferable not to give a Bar Mitzvah or wedding present on Shabbos. [Magein Avraham 306: 15] Rabbi Akiva Eiger permits sending a gift to a groom. If one does receive a gift he should have intention not to acquire it legally until after Shabbos. [Mahari Asad 83] Some poskim permit giving a gift to a non-Jew. [Makneh, Even Haezer 45; Sefer Hachaim] However, others prohibit it. [Shulchan Aruch Harav 449; Toras Chesed 27; Minchas Pittim 306. See also Kesav Sofer o.c. 59] Similarly, it is forbidden to give collateral to your friend, unless it is required to fulfill a mitzvah or for Shabbos purposes. [However,] do not say: "Here is your collateral," but simply give it to him without comment.38Rema 307: 11.
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)