Here are the top 10 thing we should focus on in the Christian life, in my opinion. There is too much to mention, so things I may not have explicitly stated would likely fit within one of these categories. For example, loving the brethren happens when you walk in the Spirit, it is feeding the sheep, warning the sheep about false teachers, wolves and false doctrine, it is betrothing the bride to Christ and warning the sheep against spiritual adultery and idolatry.
I pray this list and the accompanying verses bless you.
1. Believe the true gospel
2. Hold fast to the true gospel
3. Preach the gospel
4. Grow in grace and the knowledge of Jesus Christ/Renew your mind
5. Walk in the Spirit/live by faith/rest in Christ
6. Eat and drink Christ and feed the sheep with Christ
7. Look for Christ and his grace on every page of the bible
8. Test everything
9. Shine a light in the darkness/warn the sheep
10. Betroth the bride to Christ/warn against spiritual adultery/idolatry
1 Corinthians 15:1-4
1 Moreover, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
2 By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
3 For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures;
4 And that he was buried, and that he rose again the third day according to the scriptures:
16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
22 Let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience, and our bodies washed with pure water.
23 Let us hold fast the profession of our faith without wavering; (for he is faithful that promised;)
6 I marvel that ye are so soon removed from him that called you into the grace of Christ unto another gospel:
7 Which is not another; but there be some that trouble you, and would pervert the gospel of Christ.
8 But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed.
9 As we said before, so say I now again, if any man preach any other gospel unto you than that ye have received, let him be accursed.
2 Timothy 4:2-4
2 Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all long suffering and doctrine.
3 For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears;
4 And they shall turn away their ears from the truth, and shall be turned unto fables.
1 Corinthians 1:18
18 For the preaching of the cross is to them that perish foolishness; but unto us which are saved it is the power of God.
1 Corinthians 1:23-24
23 But we preach Christ crucified, unto the Jews a stumblingblock, and unto the Greeks foolishness;
24 But unto them which are called, both Jews and Greeks, Christ the power of God, and the wisdom of God.
2 Peter 3:18
18 But grow in grace, and in the knowledge of our Lord and Saviour Jesus Christ.
2 And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.
23 And be renewed in the spirit of your mind
16 This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh.
38 Now the just shall live by faith: but if any man draw back, my soul shall have no pleasure in him.
6 As ye have therefore received Christ Jesus the Lord, so walk ye in him
7 Rooted and built up in him, and stablished in the faith, as ye have been taught, abounding therein with thanksgiving.
10 For he that is entered into his rest, he also hath ceased from his own works, as God did from his.
11 Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief.
53 Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you.
54 Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day.
55 For my flesh is meat indeed, and my blood is drink indeed.
56 He that eateth my flesh, and drinketh my blood, dwelleth in me, and I in him.
57 As the living Father hath sent me, and I live by the Father: so he that eateth me, even he shall live by me.
58 This is that bread which came down from heaven: not as your fathers did eat manna, and are dead: he that eateth of this bread shall live for ever.
…Feed my sheep.
1 Peter 5:2-3
2 Feed the flock of God which is among you, taking the oversight thereof, not by constraint, but willingly; not for filthy lucre, but of a ready mind;
3 Neither as being lords over God’s heritage, but being examples to the flock.
17 That the God of our Lord Jesus Christ, the Father of glory, may give unto you the spirit of wisdom and revelation in the knowledge of him:
18 The eyes of your understanding being enlightened; that ye may know what is the hope of his calling, and what the riches of the glory of his inheritance in the saints,
19 And what is the exceeding greatness of his power to us-ward who believe, according to the working of his mighty power
8 Unto me, who am less than the least of all saints, is this grace given, that I should preach among the Gentiles the unsearchable riches of Christ
11 And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers;
12 For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ:
13 Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ:
14 That we henceforth be no more children, tossed to and fro, and carried about with every wind of doctrine, by the sleight of men, and cunning craftiness, whereby they lie in wait to deceive;
15 But speaking the truth in love, may grow up into him in all things, which is the head, even Christ:
16 From whom the whole body fitly joined together and compacted by that which every joint supplieth, according to the effectual working in the measure of every part, maketh increase of the body unto the edifying of itself in love.
1 Corinthians 2:1-2
1 And I, brethren, when I came to you, came not with excellency of speech or of wisdom, declaring unto you the testimony of God.
2 For I determined not to know any thing among you, save Jesus Christ, and him crucified.
2 Corinthians 3:6
6 Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.
17 For the law was given by Moses, but grace and truth came by Jesus Christ.
1 And after six days Jesus taketh Peter, James, and John his brother, and bringeth them up into an high mountain apart,
2 And was transfigured before them: and his face did shine as the sun, and his raiment was white as the light.
3 And, behold, there appeared unto them Moses and Elias talking with him.
4 Then answered Peter, and said unto Jesus, Lord, it is good for us to be here: if thou wilt, let us make here three tabernacles; one for thee, and one for Moses, and one for Elias.
5 While he yet spake, behold, a bright cloud overshadowed them: and behold a voice out of the cloud, which said, This is my beloved Son, in whom I am well pleased; hear ye him.
2 Peter 1:17-20
17 For he received from God the Father honour and glory, when there came such a voice to him from the excellent glory, This is my beloved Son, in whom I am well pleased.
18 And this voice which came from heaven we heard, when we were with him in the holy mount.
19 We have also a more sure word of prophecy; whereunto ye do well that ye take heed, as unto a light that shineth in a dark place, until the day dawn, and the day star arise in your hearts:
20 Knowing this first, that no prophecy of the scripture is of any private interpretation.
16 Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days:
17 Which are a shadow of things to come; but the body is of Christ.
1 John 4:1
1 Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.
1 Corinthians 11:18-19
18 For first of all, when ye come together in the church, I hear that there be divisions among you; and I partly believe it.
19 For there must be also heresies among you, that they which are approved may be made manifest among you.
2 Timothy 2:15
15 Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth.
11 These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
2 Peter 3:15-16
15 And account that the longsuffering of our Lord is salvation; even as our beloved brother Paul also according to the wisdom given unto him hath written unto you;
16 As also in all his epistles, speaking in them of these things; in which are some things hard to be understood, which they that are unlearned and unstable wrest, as they do also the other scriptures, unto their own destruction.
9 And this I pray, that your love may abound yet more and more in knowledge and in all judgment;
10 That ye may approve things that are excellent; that ye may be sincere and without offence till the day of Christ.
8 For ye were sometimes darkness, but now are ye light in the Lord: walk as children of light:
9 (For the fruit of the Spirit is in all goodness and righteousness and truth;)
10 Proving what is acceptable unto the Lord.
11 And have no fellowship with the unfruitful works of darkness, but rather reprove them.
12 For it is a shame even to speak of those things which are done of them in secret.
13 But all things that are reproved are made manifest by the light: for whatsoever doth make manifest is light.
2 John 1:7-11
7 For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.
8 Look to yourselves, that we lose not those things which we have wrought, but that we receive a full reward.
9 Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son.
10 If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed:
11 For he that biddeth him God speed is partaker of his evil deeds.
15 Beware of false prophets, which come to you in sheep’s clothing, but inwardly they are ravening wolves.
2 Peter 2:1-3
1 But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction.
2 And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of.
3 And through covetousness shall they with feigned words make merchandise of you: whose judgment now of a long time lingereth not, and their damnation slumbereth not.
2 Corinthians 11:13-15
13 For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.
14 And no marvel; for Satan himself is transformed into an angel of light.
15 Therefore it is no great thing if his ministers also be transformed as the ministers of righteousness; whose end shall be according to their works.
2 Corinthians 11:2-4
2 For I am jealous over you with godly jealousy: for I have espoused you to one husband, that I may present you as a chaste virgin to Christ.
3 But I fear, lest by any means, as the serpent beguiled Eve through his subtilty, so your minds should be corrupted from the simplicity that is in Christ.
4 For if he that cometh preacheth another Jesus, whom we have not preached, or if ye receive another spirit, which ye have not received, or another gospel, which ye have not accepted, ye might well bear with him.
38 Then certain of the scribes and of the Pharisees answered, saying, Master, we would see a sign from thee.
39 But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:
20 Notwithstanding I have a few things against thee, because thou sufferest that woman Jezebel, which calleth herself a prophetess, to teach and to seduce my servants to commit fornication, and to eat things sacrificed unto idols.
21 And I gave her space to repent of her fornication; and she repented not.
22 Behold, I will cast her into a bed, and them that commit adultery with her into great tribulation, except they repent of their deeds.
3 So then if, while her husband liveth, she be married to another man, she shall be called an adulteress: but if her husband be dead, she is free from that law; so that she is no adulteress, though she be married to another man.
4 Wherefore, my brethren, ye also are become dead to the law by the body of Christ; that ye should be married to another, even to him who is raised from the dead, that we should bring forth fruit unto God.
1 Corinthians 10:14
14 Wherefore, my dearly beloved, flee from idolatry.
1 John 5:20-21
20 And we know that the Son of God is come, and hath given us an understanding, that we may know him that is true, and we are in him that is true, even in his Son Jesus Christ. This is the true God, and eternal life.
21 Little children, keep yourselves from idols. Amen.