Because of the hope of Israel (heineken tēs elpidos tou Israel). Genitive with preposition heineken. The hope of the Messiah is his point as in Act 26:6.
I am bound with this chain (tēn halusin tautēn perikeimai). This old verb means to lie around as in Luk 17:2; Heb 12:1. But it is also used as the passive of peritithēmi, to place around with the accusative of peritithēmi retained. It is a transitive passive. Paul does not lie around the chain, but the chain lies around him, a curious reversal of the imagery (Robertson, Grammar, p. 815).