Bible Gateway:
https://www.biblegateway.com/passage/?search=Philippians+2&version=AMP
Bible Hub Commentary Philippians 2:14-16
https://biblehub.com/commentaries/philippians/2-14.htm
Ellicott's Commentary for English Readers
(14) Without murmurings and disputings.—St. Paul seems purposely to leave this precept in perfect generality, so as to apply to their relations, both to God, and man. We observe, however, that the word “disputings” is mostly used of objections and complaints in word. It is applied to the inner strife of the heart. In either case it seems mainly to indicate intellectual questionings. Similarly, the word “murmuring” is used of outward wranglings of discontent proceeding not so much from the mind, as from the heart.

(15) Blameless and harmless.—“Blameless” as to external law and judgment (as in Luke 1:6; 1Thessalonians 2:10); “harmless” in internal purity and simplicity (as in Matthew 10:16, “harmless as doves;” and Romans 16:19).

The sons of God, without rebuke.—The word “without rebuke” is elsewhere used to signify “unblemished.”

Lights.—Properly, luminaries; so used in the Old Testament, and probably in Revelation 21:11. Christians are as the lesser lights of heaven, dim in comparison with the Sun of Righteousness, perhaps shining by His reflected light, and seen only in the night of this life, till He shall rise on us again in the “day of Christ” spoken of in the next verse.

(16) Holding forth the word of life.—This translation seems correct, and the reference is to the comparison above. There may, indeed, be (as has been supposed) a reference, involving a change of metaphor, to the holding forth of a torch, for guidance, or for transmission, as in the celebrated torch race of ancient times. But this supposed change of metaphor is unnecessary. The “luminaries” hold forth their light to men, and that light is the “word of life.” Note the same connection in John 1:4, “In Him was life, and the life was the light of men.”

The word of life.—The phrase “the word of life” is remarkable. Here it signifies, of course, the gospel of Christ. But the gradual progress of this expression should be noted. Of Him His disciples declared that He “has the words” (i.e., the expressed words; see Note on Ephesians 6:17) “of eternal life” (John 6:68); He Himself goes further, and declares that His words are themselves spirit and life (John 6:63); here the gospel, as giving that knowledge of God and of Jesus Christ which is “eternal life” (John 17:3), is a “word of life;” and all these lead up to the final declaration that He Himself is “the Word of life” (1John 1:1).