There is repeated emphasis in the Bible on the oneness of divine authority.
For example, Jesus insisted that there is only “one father” (Mt. 23.9) and “one shepherd” (Ezek. 34.23; 37.24; Jn. 10.16). Paul affirmed that there is “one god” (1 Tim. 2.5; Eph. 4.6) and “one lord” (Eph. 4.5; cf. Zech. 14.9), etc. (see  below).
On other occasions, however, Bible writers apply these terms of authority to more than one individual. The Hebrews author wrote that we “have had human fathers (note the plural) who corrected us” (Heb. 12.9).
The night of Jesus’ birth, there were “shepherds living out in the fields” (Lk. 2.8). Too, the church is overseen by men called, “shepherds” (Eph. 4.11, ESV; cf. Acts 20.28).
The psalmist described deity as the “god of gods” (Ps. 136.2; cf. Deut. 10.17), and even characterized human beings with the appellation, “gods” (Ps. 82.6; cf. John 10.34).
Sarah called her husband, “lord” (Gen. 18.12) as a term of respect, stemming from her “gentle and quiet spirit” (1 Pt. 3.4-6). And note several other instances of the use of the term, lord (i.e., master, owner), in Scripture, where God is not the referent (Mt. 10.24-25; Gal. 4.1; Lk. 16.3, 5; Eph. 6.5).
If Scripture alludes to many fathers, shepherds, gods, lords, etc., then why do inspired authors maintain there is only one who is worthy of these designations?
1 Corinthians 8
Paul himself addresses this seeming discrepancy in 1 Corinthians 8. He first explains that “there is no other god but one.” From this, it is clear that the term, "one," is meant to signify exclusivity — the “singularity of something” (Mounce, 485) “to the exclusion of others” (Vine, 446). Indeed, “no other god” leaves room for one and one alone (cf. Isa. 44.8).
How, then, can Scripture apply the same term to others?
“even if there are so-called gods, whether in heaven or on earth (as there are many gods and many lords), yet for us there is one god, the father, of whom are all things, and we for him; and one lord Jesus Christ, through whom are all things, and through whom we live” (1 Cor. 8.5-6).
In other words, authoritative terms like, god, lord, shepherd, and father, may be attached to non-divine beings in an accommodative (“so-called”) fashion for the sake of linguistic convenience, but Christians (“for us”) recognize only one legitimate authority in the universe.
This is why the Bible says that Jehovah is the “only god” (Jude 25; 1 Tim. 1.17, ESV). Men may be called, "god," in a manner of speaking, but Jesus indicated that Jehovah is the “only true god” (John 17.3).
In that light, no “so-called” father, shepherd, god, or lord, can claim any authority of himself, for “it is not in man who walks to direct his own steps” (Jer. 10.23).
Rather, since Jesus possesses “all authority…in heaven and on earth” (Mt. 28.18) — which leaves no authority for anyone else, except the father who gave him that authority (1 Cor. 15.27) — therefore, human “fathers,” “shepherds,” etc., can only exercise legitimate authority “through” him (“through whom we live”). In other words, all decisions we make must comply with his authority (Col. 3.17) and be done for his glory (1 Cor. 10.31).
Thus, when a human father asks his children to engage in activity which defies the one father’s authority, that human “father” must be disobeyed, for he possesses no fatherly authority of himself, but may only exercise authority “in the lord” (Eph. 6.1; cf. Acts 4.19; 5.29). The heavenly father is the “only true” father in the home (cf. Isa. 63.16); the human father, so-called, is just an emissary sent to do the true father’s business (cf. Lk. 2.49).
Now, certainly, there is a sense in which we may think of God as the chief God, Father, Lord, and Shepherd (cf. 1 Pt. 5.4), insofar as we may only exercise authority under him (for he is “over all” — Rm. 9.5), and, indeed, God has given men responsibilities over this world (cf. Gen. 1.26; 9.2; Psalm 8.6-8; 115.16).
But it is the express aim of these passages to establish the fact that there is only one rightful authority in the universe — God, the “only potentate” (cf. 1 Tim. 6.15) — “through whom” all those who exercise authority in this world must comport themselves (Mt. 6.10). Our “so-called” authority is not ours, but his. We may only act as he authorizes us to act.
In every domain of life, then, whether as a “so-called” father, husband, a shepherd of the church (etc.), let us conform our every decision to his absolute will. His authority is the only authority that has the right to exist (Ex. 19.5; Job 41.11; Ps. 24.1; 1 Cor. 10.26).
“Yours, O Lord, is the greatness,
The power and the glory,
The victory and the majesty;
For all that is in heaven and in earth is Yours;
Yours is the kingdom, O Lord,
And You are exalted as head over all.” (1 Chron. 29.11).
 I have written these terms without capitalization for the sake of replicating the way the inspired writers wrote, who did not make use of the convention of reverential capitalization (capitalizing nouns and pronouns associated with deity). Though this convention is quite appropriate, abandoning it in the citation of these particular verses will help to take our minds back into the original framework of the argument these authors were making on this matter.
For example, instead of distinguishing between one Father and many fathers, the Lord insisted that there is only one father. This makes his argument even stronger in thrust. Instead of suggesting that the Father has his authority, while fathers have theirs, the Lord is arguing that there is only one true father, who possesses all the authority of fathers.