Biblical use of the verb hayah differs in many respects from our "to be," "to happen," "to become," or Greek eimí, gígnomai. Study of its use demands an integration of cognitive semantics, discourse analysis and literary scrutiny. The meaning "to fall" (Arabic hawa), preserved in Job 37:6 (cf. Eccl 11:3), forms the backdrop for the noun howah ("calamity;" Isa 47:11; Ezek 7:26; cf. Pro 19:13; Job 6:2; 30:10; cf. some uses of Akkadian ewûm). The use of hayah in the meaning "to be," "to happen" results from semantic bleaching, much like the use of Arabic waqa?a "to fall" in the meaning "to happen," and of verbs indicating stability (kun, kana) in Phoenician and Arabic, to indicate existence or subject-predicate relation. The thesis of the present paper is that in Biblical Hebrew bleaching has resulted in a wide meaning potential (cf. Latin incido), in which, e.g., dynamics, salience and sometimes even activity, play an important role. In Exodus 19:16 wyhy ... bhywt ... wyhy implies much more than "happening" / "occurrence" (cf. v. 19; Gen 1:8). In Gen 29:17 a hayah clause follows a verbless clause and thus does not serve as time indication nor as a mere copula. wyhy forms are often used to draw the attention, like 1 Sam 1:2 (Joosten 1997:78). In some of these cases hayah could mark highlighting ("higher salience"), but in other cases (Exod 3:14; 1 Sam 1:18; Gen 4:8) the semantic nuance still is far stronger.