I use hard carnauba wax (it comes in bar form like a big bar of soap) on a loose buff for the most all woods that won't take a finish easily.
Ebony, King Wood, Lignum Vitae, Cocobolo, & probably most of the Rose Wood family have so much oil in the wood that it is difficult to impossible to get a finish to dry in those types of wood.
I use Walker Wax on the blade as it protects the blade against spittle which Ren wax doesn't.
If you don't think spittle is a problem; then check your knives that have been laying open on a display table after you have talked across the table to customers for three days of a big show.
Dale