God tells us in His Word what we should avoid:
1 Tim 6:20 – Guard what has been entrusted to you (the gospel). Turn away from Godless chatter and the opposing ideas of what is falsely called knowledge.
Titus 3:9 – But avoid foolish controversies and arguments and quarrels about the law, because these are unprofitable and useless.
2 Thes 3:14 – And if anyone does not obey our word in this epistle, note that person and do not keep company with him, that he may be ashamed.
On a positive note, God also tells us what we should be doing as believers in the body of Christ:
Mt 7:`12 – Therefore, whatever you want men to do to you, do also to them, for this is the Law of the Prophets.
2 Cor 6:17 – Therefore come out from among them and be separate, says the Lord. Do not touch what is unclean and I will receive you.
1 Cor 10:32 – Give no offense, either to the Jews, or the Greeks (Gentiles) or to the church of God (Christians).
1 Thes 5:14 – And we urge you, brothers, warn those who are idle, encourage the timid, help the weak, be patient with everyone.
2 Tim 2:24 – And the Lord’s servant must not quarrel; instead, he must be kind to everyone, able to teach, not resentful.
Mt 10:16 – I am sending you out like sheep among wolves. Therefore be shrewd as snakes and as innocent as doves.
Jude 22-23 – And on some have compassion, making a distinction; but others save with fear, pulling them out of the fire, hating even the garment defiled by the flesh.
1 Pet 5:8 – Be sober, be vigilant; because your adversary the devil walks about like a roaring lion, seeking whom he may devour.
Obeying God’s commands concerning personal relationships may not eliminate all the strife and discord in your life but it’ll remove 90% of it. God has also promised to give us His peace which will allow us to live in harmony with everyone. The more commands we follow the more our lives emulate Christ, which is God’s will for us. This is what we call sanctification which is an ongoing process while we’re down here on earth. When we get to heaven God will complete our transformation (glorification) so that we cannot sin and we can fellowship with God forever.