Psalm 28/Notes/Phrasal.v. 7.536677

• The preposition בְּ in בּוֹ ([my heart has trusted] in him) "introduces the person or thing, which is the object of a mental act, e.g. הֶֽאֱמִין בְּ to trust in (to cleave trustingly to) somebody or something; בָּטַח בְּ to have confidence in...".
• The preposition מִן in וּמִשִּׁירִי (and out of my song >> and with my song) carries its prototypical use as source as well as the notion of instrumentality. In other words, it is a מִן of source and, semantically, because the source is involved as the instrument of an accomplishment, instrumentality is semantically justifiable. Perowne's rendering expresses this notion: "out of my song (>> with my song) I give him thanks." See The meaning of וּמִשִּׁירִי in Ps 28:7b for further information.