מִזְמ֗וֹר לְדָ֫וִ֥ד הָב֣וּ לַֽ֭יהוָה בְּנֵ֣י אֵלִ֑ים הָב֥וּ לַ֝יהוָ֗ה כָּב֥וֹד וָעֹֽז׃
אַ מזמור פֿון דָוִדן. גיט צו ה׳, איר מאַכטיקע, גיט צו ה׳ כּבֿוד און שטאַרקײט,
Rashi
Prepare for the Lord Heb. הבו. Prepare for the Lord and prepare for Him, you sons of the mighty of the land. From here we derive the ruling that [for the first blessing of the Amidah prayer] we should say the blessing אבות, the Patriarchs (Meg. 17b, R.H. 32b, Mid. Ps. 29:2). But Menachem (p. 68) associated הבו as an expression of giving.
Rashi
prepare for the Lord glory and might From here we derive that [for the second blessing of the Amidah prayer] we should say the blessing of גבורות, mighty deeds.