Necessary Inference
We do not know who first used the expression necessary inference but its equivalent found in works of Aristotle and other Greek teachers of the reasoning process. When evidence is collected and we draw a conclusion, the conclusion is our inference. It is necessary to the extent the evidence demands it. There is a colloquial use of inference, i.e., surmise, guess, hint, etc. but this is not its use in legitimate discussion of reasoning and Bible authority.
I would charitably assume that any gospel preacher knows that God made His will known to man by sending His Holy Spirit to chosen messengers, to guide them in speaking and writing what He wanted us to know. It seems uncharitable to have to say that this inspired message is understandable, for Gods process of imparting information is thwarted if it is not. But how does man understand the Bible? Exactly as he understands any other written message. He must be able to read — to translate words into mental images. He accumulates information, contemplates, reasons, and draws conclusions. These conclusions are inferred in the strict and logical meaning of the term.
The inspired history written by Luke records that Peter commanded some people in Jerusalem to repent and be baptized. This is related to Gods promise to those afar off. We have sufficient evidence to conclude that this was a portion of the message Christ wanted proclaimed to every creature so we necessarily infer that we also must repent and be baptized. Our understanding is the result of a process of human reasoning upon the word God.
That reasoning can be true and productive of good (2 Tim. 2:15; Eph. 3:4) or it can be faulty and productive of bad (2 Pet. 3:16); depending upon the attitude and purpose one has in approaching Gods word (Jn. 7:17). We may infer without sufficient evidence — and that is why evidence is prefixed to inference when discussing Bible interpretation. We are individually responsible before our use of His message.
But the miracle of revelation in the giving and confirming, not in the process of reception. God made the man, for whom He made the word.
Is a necessary inference binding upon the conscience? Yes! When careful study of Gods word impresses with an inescapable conclusion, ever conveyed, you must receive it or be untrue to yourself and to God.