I think it's pretty well known that there's an idea that 70 years from Adam's life were given to Dovid Hamelech, which is why he lived to 930 and not 1000. A source that I found for this is Zohar Vayishlach 188a.
The next part of the Zohar points out that Avraham lived 5 years short (of Yitzchak's lifespan of 180), Yaakov 28 (from Avraham's lifespan of 175), and Yosef 37 (from Yaakovs lifespan of 147). This also adds to 70, telling us they all gave Dovid his 70 year lifespan.
How are both these two statements true (since Dovid lived to 70 not 140)? Or are they in conflict.