Paul can hardly be accused of mincing his words. He is an apostle, knows the truth, and says it clearly and unapologetically. Sometimes he uses sentences that are so long we struggle a bit to follow his discussion, but the Greek often has clues that help.
In describing the false teachers, Paul says that “some” people (τινες) will depart from the faith, and then follows with a series of participles that tie the argument together. When the NIV and NET start a new sentence at 3, and the NLT starts a new paragraph, they break the flow of thought and these participles become key in understanding Paul.
- Their departure is due to their devotion (προσέχοντες) to deceitful spirits and demonic teachings.
- Their consciences are seared (κεκαυστηριασμένων).
- They forbid people to marry (κωλυόντων γαμεῖν).
- They require abstinence from foods (ἀπέχεσθαι βρωμάτων).
All four of these constructions are descriptions of the false teachers, despite the break in English sentences.
Another point worth making has to do with the omitted word before ἀπέχεσθαι. γαμεῖν is a complementary infinitive, or else you could view it as a noun replacement acting as the direct object of κωλυόντων. It is what is forbidden.
But it makes no sense to view γαμεῖν and ἀπέχεσθαι as both completing κωλυόντων; otherwise, you end up with the nonsensical “forbidding … to abstain.” There has to another participle that has been omitted. The translations supply words such as “require” (ESV), “order” (NIV), “demand” (HCSB), “advocate” (NASB, in italics), and “commanding” (KJV). The NLT has the periphrastic, “They will say it is wrong to be married and wrong to eat certain foods.”
Ellipsis can be frustrating, but we do it in English all the time, and I assume it is characteristic of many if not all languages. Context will help you fill in the blanks.