A friend recently asked me how one goes about deciding whether a doctrine is correct or not. There are at least four answers to this question and an important caveat.
First, as my friend was already doing, one asks one's brethren for assistance. Scripture says:
Proverbs 11:14 Where no counsel is, the people fall: but in the multitude of counsellors there is safety.
Proverbs 15:22 Without counsel purposes are disappointed: but in the multitude of counsellors they are established.
Proverbs 24:6 For by wise counsel thou shalt make thy war: and in multitude of counsellors there is safety.
Two are better than one; because they have a good reward for their labour. For if they fall, the one will lift up his fellow: but woe to him that is alone when he falleth; for he hath not another to help him up. Again, if two lie together, then they have heat: but how can one be warm alone? And if one prevail against him, two shall withstand him; and a threefold cord is not quickly broken.
Second, in particular, one should seek advice not only of one's brethren in general but of those who have the duty of being teachers in spiritual things. Thus, women should learn from their husbands, and the husbands should learn from the elders.
1 Corinthians 14:34-35
Let your women keep silence in the churches: for it is not permitted unto them to speak; but they are commanded to be under obedience, as also saith the law. And if they will learn any thing, let them ask their husbands at home: for it is a shame for women to speak in the church.
2 Timothy 2:2 And the things that thou hast heard of me among many witnesses, the same commit thou to faithful men, who shall be able to teach others also.
2 Timothy 2:24-26
And the servant of the Lord must not strive; but be gentle unto all men, apt to teach, patient, in meekness instructing those that oppose themselves; if God peradventure will give them repentance to the acknowledging of the truth; and that they may recover themselves out of the snare of the devil, who are taken captive by him at his will.
The third was is hinted at implicitly in the previous answers:
Romans 15:4 For whatsoever things were written aforetime were written for our learning, that we through patience and comfort of the scriptures might have hope.
Of whom we have many things to say, and hard to be uttered, seeing ye are dull of hearing. For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not of strong meat. For every one that useth milk is unskilful in the word of righteousness: for he is a babe. But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to discern both good and evil.
John 5:39 Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me.
Acts 17:11 These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
The fourth answer is prayer to God for wisdom:
1 John 2:27 But the anointing which ye have received of him abideth in you, and ye need not that any man teach you: but as the same anointing teacheth you of all things, and is truth, and is no lie, and even as it hath taught you, ye shall abide in him.
James 1:5 If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him.
The crucial caveat is that we need to be content with our limitations in the present life.
Titus 3:9 But avoid foolish questions, and genealogies, and contentions, and strivings about the law; for they are unprofitable and vain.
1 Timothy 6:3-6
If any man teach otherwise, and consent not to wholesome words, even the words of our Lord Jesus Christ, and to the doctrine which is according to godliness; he is proud, knowing nothing, but doting about questions and strifes of words, whereof cometh envy, strife, railings, evil surmisings, perverse disputings of men of corrupt minds, and destitute of the truth, supposing that gain is godliness: from such withdraw thyself. But godliness with contentment is great gain.
1 Corinthians 13:12 For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.
Hebrews 13:5 Let your conversation be without covetousness; and be content with such things as ye have: for he hath said, I will never leave thee, nor forsake thee.
So, then, to sum up my response, one should seek wisdom from one's brethren as you, the reader, are already doing. Seek wisdom from your elders or, if you are a woman, from your believing husband. Most importantly, search the Scriptures and above all pray to God for wisdom.
When you reach an impasse in your understanding, of course you may continue to pray for wisdom, but strive as well to be content. Because our heavenly Father knows your needs, even before you ask (Matthew 6:7-8), and does graciously work all things together for the good of the elect (Romans 8:28), you can be assure that God will give you all the understanding that you need, even if that leaves one or more difficult doctrinal questions unanswered for the time being.
Philippians 4:19 But my God shall supply all your need according to his riches in glory by Christ Jesus.