Angels were created before human beings, and are "greater in power and might" (Job 38:6-7; II Peter 2:11). Nevertheless, the Bible declares them to be "ministering servants... for them who shall be heirs of salvation" (Hebrews 1:14).
One wonders if this might be a reason that some angels, including Lucifer, rebelled against God. Might they have been informed that a new race of beings in God's own image would be created by the Lord, a race with lesser capacity and strength, but whom angels would serve? We do not know, but we can be sure that fallen angels seek not to serve the "heirs of salvation," but rather to hinder our relationship with the Lord Jesus Christ. "My brethren, be strong in the Lord, and in the power of His might. Put on the whole armor of God, that ye may be able to stand against the wiles of the devil. For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places" (Ephesians 6:10-12).
In God's economy, strength and authority (including His own), are used to serve rather than dominate. "He that is greatest among you shall be your servant... The Son of man came not to be ministered unto, but to minister, and to give His life a ransom for many" (Matthew 23:11; 20:28). Believers serve a Lord who Himself bears the heart of a servant. We serve a Servant, as it were. The Lord Jesus is infinitely greater than we are, and He is certainly the Master to whom we bow in humility and submission. However, had He not first served by coming "not to be ministered unto, but to minister," we would never have known or had a relationship with Him. He had to be our Lamb before He could be our Lord, and the heart of a servant still beats in His glorious chest.
"And one of the elders saith unto me, Weep not: behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof. And I beheld, and, lo, in the midst of the throne and of the four beasts, and in the midst of the elders, stood a Lamb as it had been slain" (Revelation 5:5-6).
We shall forever be awed by our Lord's greatness and majesty. And we shall forever be awed by His lowliness of heart and humility. Both perspectives of God are required in order to know Him rightly. The Lord Jesus is both the Lion and the Lamb, and those who know Him well are awed by His greatness, and amazed by His lowliness. Faithful angels reflect this dual nature of God, serving those who are lesser than themselves. Faithful humans do the same, heeding the Apostle Paul's command to "esteem others as better than ourselves" (Philippians 2:3). Few truths about our Lord and ourselves more sanctify our hearts unto the holiness whereby we know God as He is, and subsequently live as the servants of the great Servant.
"Take My yoke upon you and learn of Me, for I am meek and lowly in heart, and ye shall find rest unto your souls."