I’ve changed the title of your thread a bit to help facilitate discussion. 
(I only switched a couple of word positions to make it a question.)
IF scripture is to be believed, one day your father will accept Christ, if not in this life, surely in the life-to-come. Hallelujah!
Every knee shall bow and every tongue shall joyfully proclaim allegiance to Jesus and confess that He is Lord!
They have stumbled over the stumbling stone–but not so as to fall, have they?
[size=150]***MAY IT NEVER BE!!!***[/size] 
There are a lot of scriptural promises about the salvation even of rebel Israel, but also especially of faithful Israel who hold to the Torah out of love and devotion to God. There is not one word spoken against such people in the scriptures, and quite a few things to the effect that at the final coming of the Messiah they will recognize and accept Him immediately even if weeping over how they had previously treated Him.
Righteous Israel are still sinners just like all of us, and still in need of salvation; but they’re native to the vine and I don’t expect there will be much problem from them (or with them). It’s a technical issue with them, not one of stubbonness as to sin–they may even be (and often are) holding off out of concern for not being led astray from the sole worship of God. When the Presence of YHWH finally returns, He will be Who they were looking for, and they will be among the first of His sheep not the goats.
So keep good hope: your father’s Judaism isn’t a barrier. Any sins he is impenitent of might be a barrier (or maybe not depending on why he is impenitent, which may be due to natural heredity and so slated to be healed). But that’s an issue between him and God, and if he really is orthodox he should be pretty well aware of them already whatever they are. God will keep after him about those–just like with any of the rest of us.