Failure to tithe is not a sin, unless you are in a different church than I ever belonged to. I guess it goes along with the “never forget to pay the “power company” for they can turn off your “salvation”.
For sake of a better word, I used ‘sin’ as what I consider it when someone like Cruz speaks as often and passionately as he does and then gives almost nothing to the church. You may have a different opinion (I generally like and respect Cruz) but it certainly doesn’t make me trust him like I would if I saw that he and his Goldman Sachs VP wife gave generously to their church.