We have an altar (εχομεν θυσιαστηριον). We Christians have a spiritual altar (θυσιαστηριον), not a literal one (Hebrews 7:13). This metaphor is carried out.

Whereof (εξ ου). Our spiritual altar.

The tabernacle (τη σκηνη). Dative case with λατρευοντες (serve), σκηνη being used for "the whole ceremonial economy" (Vincent) of Judaism.