Jesus seems pretty detail-oriented to me. Jesus said, “For truly, I say to you, till heaven and earth pass away, not an iota, not a dot, will pass from the law until all is accomplished.” (Matthew 5:18; see Luke 16:17) He said, “But not a hair of your head will perish.” He said, “Woe to you, scribes and Pharisees, hypocrites! for you tithe mint and dill and cummin, and have neglected the weightier matters of the law, justice and mercy and faith; these you ought to have done, without neglecting the others.” (Matthew 23:23) To many, an iota and a dot and a hair and mint and dill and cummin are “petty details” yet Jesus cared about them enough to mention them.
Consider Jesus’ two-step cure of the blind man and how, though the blind man himself may have been quite happy with just having some of his sight restored and being able to see his fellow men though they looked to him like trees, Jesus was not content until the man “saw everything clearly”:
And some people brought to [Jesus] a blind man, and begged him to touch him. And he took the blind man by the hand, and led him out of the village; and when he had spit on his eyes and laid his hands upon him, he asked him, “Do you see anything?” And he looked up and said, “I see men; but they look like trees, walking.” Then again he laid his hands upon his eyes; and he looked intently and was restored, and saw everything clearly. (Mark 8:22-25)
The apostles Peter and John celebrated their common faith in Jesus Christ with the Samaritans who had received the word of God and been baptized in the name of Jesus but they were still eager that what they saw as lacking in their formation be corrected and “came down and prayed for them that they might receive the Holy Spirit … [and] laid their hands on them and they received the Holy Spirit.” (Acts 8:15,17)
Priscilla and Aquila celebrated their common faith in Jesus Christ with Apollos but they were still eager that what they saw as lacking in his formation be corrected and “took him and expounded to him the way of God more accurately.” (Acts 18:26)
Paul celebrated their common faith in Jesus Christ with the disciples he found in Ephesus, who had only received John’s baptism, but he was still eager that what he saw as lacking in their formation be corrected and baptized them in the name of the Lord Jesus and laid his hands on them and they received the Holy Spirit. (See Acts 19:1-6)
If the New Testament writers were content just celebrating their common faith in Jesus Christ with their Christian readers, with their shared understanding of “the first principles of God’s word” (Hebrews 5:12) and “the elementary doctrines of Christ” (6:1) and not also eager that what they saw as lacking in their formation be corrected, then most of the New Testament epistles would never have been written. They wrote so that their Christian readers would all attain “the unity of the faith” (Ephesians 4:13), even in what some might call the “petty details.”