Here are 2 Bible verses about deadbeat dads from the Old and New Testaments of the Holy Bible (King James Version), sorted from most to least relevant.
1 Timothy 5:8 KJV
But if any provide not for his own, and specially for those of his own house, he hath denied the faith, and is worse than an infidel.
Ephesians 6:4 KJV
And, ye fathers, provoke not your children to wrath: but bring them up in the nurture and admonition of the Lord.