The simple answer is nothing keeps God from saving whom He desires to save; He is God and accomplishes all His desires.
One major thing to focus on is letting scripture interpret scripture. Let the simple interpret what appears to be complex or contrary to your liking.
Job 23:13
But He is in one mind,and who can turn Him? Yea, His soul desires, and He does it.
Isaiah 46:10
declaring the end from the beginning, and from the past those things which have not been done, saying, My counsel shall rise; and, I will do all My desire;
Nebuchadnezzar learned the hard way that God does what He wants to do, puts people in the places he wants them and fulfills all His desires
Daniel 4:34-35
34 And at the end of the days ,I, Nebuchadnezzar, lifted up my eyes to the heaven, and my understanding returned to me, and I blessed the Most High. And I praised and honored Him who lives forever, whose dominion is an everlasting dominion, and His kingdom from generation and generation.
35 And all those living in the earth are counted as nothing. And He does according to His will among the army of Heaven, and among those living in the earth. And no one is able to strike His hand or say to Him, What are You doing?
Isaiah 55:11
so shall My Word be, which goes out of My mouth; it shall not return to Me void, but it shall do that which I please, and it shall prosper in that which I sent it to do
2 Corinthians 2:14-17
14 But thanks be to God, the One always leading us in triumph in Christ, and the One revealing through us the fragrance of the knowledge of Him in every place.
15 For we are a sweet smell to God because of Christ in the ones being saved, and in the ones being lost
16 to the ones, an odor of death unto death, and to the ones, an odor of life unto life. And who is sufficient for these things?
17 For we are not as the many, peddling the Word of God; but as of sincerity, but as of God. We speak in Christ before God.
Romans 9:19
You will then say to me, Why does He yet find fault? For who has resisted His will?
Romans 9:20
Nay, rather, O man, who are you, the one answering back to God? Shall the thing formed say to the One forming it, Why
did You make me like this?
1 Timothy 2:4
who desires all men to be saved and to come to a full knowledge of truth.
Note: if God wanted every single individual to be saved and come to the knowledge of the truth then every single individual would be saved; but we know from Revelation 7:9 that God saved All that the Father gave to Jesus John 6:37 who came out of every nation, even tribes, peoples and languages which defines “ all men” in
1 Timothy 2:4
In 1 Timothy 2, The Apostle Paul is advocating for the prayer of “all men” to be saved including Kings and all the (ones) in pre-eminence which defines the “all men” as classes of men and points to the fact that God is not a respecter of persons and desires “all men” to be saved. Acts 10:34
Romans 9
Explains that God wants to show His wrath and show forth His power on vessels fitted out by Him for destruction ; so that His name might be publicized in all the earth in order that He make known the riches of His glory on vessels of mercy which He prepared beforehand for glory.
Romans 9 also reveals God has the right to do with His creation as He sees fit and He makes himself and forms himself both vessels of wrath fitted out for destruction and vessels of mercy.
Romans 9:15,18
For He said to Moses, “I will have mercy on whomever I will have mercy, and I will pity whomever I pity.
So, then, to whom He wills, He shows mercy; but to whom He wills, He hardens
Proverbs 16:4
Jehovah has made all for His purpose, yea, even the wicked one for the day of evil things.
Proverbs 21:1
¶ As streams of waters, the king’s heart is in the hand of Jehovah; He extends it wherever He desires.
John 3:8
Says the Spirit of God breathes where it desires and that desire to breathe
Sovereignly is directed…. at everyone being generated by God of the Spirit from above.
The Spirit breathes sovereignly on All that The Father gives to Jesus John 6:37 The Spirit gives them a new heart unto belief of the Gospel of Grace, The Gospel of Christ and causes them to come to Jesus through the gift of the Spirit believing that salvation is conditioned on His atoning shed blood and His imputed perfect righteousness alone without any effort or contribution from those he died for chosen from before the foundation of the world. God promises to save His people and Jesus will not lose one of them; but will raise it up in the last day. Romans 3:20-27 Matthew 1:21
Ephesians 1 Ephesians 2
Romans 8:28-30
Luke 18:13
And the tax collector, standing afar off, would not even lift up his eyes to Heaven, but smote on his breast, saying, God, be merciful to me, the sinner!
Luke 23:39-43
39 And one of the hanged criminals blas- phemed Him, saying, If You are the Christ, save Yourself and us.
40 But answering, the other rebuked him, saying, Do you not fear God, for you are in the same judgment?
41 And we indeed justly, for we receive things worthy of what we did. But this One did nothing amiss.
42 And he said to Jesus, Lord, remember me when You come in Your kingdom.
43 And Jesus said to him, Truly I say to you, Today you will be with Me in Paradise.
John 6:37
37 All who the Father gives to Me shall come to Me, and the one coming to Me I will not cast out, not ever,
38 for I have come down out of Heaven, not that I should do My will, but the will of Him who sent Me.
39 And this is the will of the Father sending Me, that of all that He has given Me, I shall not lose any of it, but shall raise it up in the last day.
Scripture interprets Scripture 