The fact that “God’s Will” will be done and that “His predestination” to Save the World Will come to pass in time may be inferred too from the verse below:

‘In Christ we too have been claimed as God’s own possession, since we were predestined according to the “One purpose” of Him Who accomplishes “all things” according to the counsel of “His Will”.’

(Ephesians 1 :11)

The saving of believers is Christ’s “first fruits” not His “only fruits”. (the verse below highlights this as well):

“or even as in Adam “all” (all men) die, so also in the Christ “all” (the same ‘all men’ who died due to Adam) shall be made “alive” (Resurrected to live with Him eventually though they may die secondly in the ‘second death’), and each in his proper order (not saved or resurrected to life at the “same” time – an ordering is evident), a first-fruit Christ, afterwards those who are the Christ’s, in His presence (Christ is the Resurrected Lord Who gives this life to those who are “His” first),” (1 Corinthians 15:22 – 23)

I’m not adding or stretching the verse too far since the “full intent of His Will” to “Gather in One”, yes in “One” not “some” things or Christian things but rather “all” things is written (literally) below (this is what “all” wisdom & understanding the “mystery” or “secret” of “His Will” as written in His Word means – that is, understanding His Will to Save all & how He accomplishes it through Christ alone!):

“that He lavished on us. With “all” wisdom and understanding, He had made known to us the “mystery” (secret) of “His Will” according to His good pleasure, which He “Purposed” in Christ, to be put into effect when the “times” reach their fulfillment—to gather in “One” all things in heavens and on earth in Christ – in Him.” (Ephesians 1:8,9,10)

Correlate the above too with the conclusion in 1 Corinthians 15 (the real end of the Bible) where God Will become “All in All” (no more enemies remain) thus achieving the fulfillment of His “One Purpose” to “Save the World” by “His Will”!

“and when the “all things” (not some/Christians things only) may be subjected to Him, then the Son also Himself shall be subject to Him, Who did subject to Him the all things, that God may be the “all in all”.” (1 Corinthians 15:28)

P/S:

1. The only “One Purpose” of God as to Why He came as Lord Jesus Christ is to “Save the World” (John 3:17) in different “times” (plural in Ephesians 1:10 above – indicating that not all saved at the same “time”; none shall perish – remain perished eternally – To Save All). These different “times” (plural – kairois) moments for the Salvation of “each one” (that is, the ransom paid by Christ being testified for each one) in the “all” is literally described (too) in the famous verse below:

“Who (Jesus) did give Himself a ransom for “all” — the testimony (to be testified) in its own “times” (kairois).” (1 Timothy 2:6)

2. This “secret” (mystery) of “God’s Will” was not made known (hid) to men in the “past ages (aionon)” but has been revealed now to His saints (literally) as the verse below tells us (meat doctrine):

“the secret (mystery) that hath been “hid” from the ages (aionon) and from the generations, but now was manifested to His saints,” (Colossians 1:26)

The effect of knowing this secret is to present “every” man (all men) not some or believing ones only “perfect” in “Christ Jesus” meaning that in “time”, Christ Will perfect all men (every man) according to the secret of His Will. Here’s the continuation of the verse above describing this eventual effect (note the “all” wisdom again):

“Whom we proclaim, warning every man, and teaching every man, in “all” wisdom, that we may present “every” man perfect in Christ Jesus,” (Colossians 1:28)

3. The verses below beautifully and literally describe “all the points above” succinctly (no need for me to ‘repeat’ the explanation of this secret/mystery of “His Will” again):

“that by revelation He made known to me the “secret”, according as I wrote before in few [words] — in regard to which ye are able, reading [it], to understand my “knowledge” in the “secret” of “Christ”, which in other generations was “not made known” to the sons of men, as it was now revealed to His holy apostles and prophets “in the Spirit” (that’s why not very bluntly written in Scripture – Wisdom of God) — that the “nations be fellow-heirs” (all people), and of the “same body” (of initial believers/Christians), and partakers of His promise (to save the World) in Christ (alone), through the Good News (Gospel), “ (Ephesians 3:3 – 6)

4. Nothing can “stop/stand against” God’s Will ‘eternally’. Everything will come to pass in its appropriate “times”. Don’t be deceived by men who say otherwise since the verse below is “literally” clear on this (special highlight: The verse below proves that His “One Purpose” to “Save the World” will come to pass regardless!):

“I make known the end from the beginning, from ancient times, what is still to come. I say, ‘My “Purpose” will stand, and I will do “all” that I please.’” (Isaiah 46:10)

5. A warning. Peter’s “3:16” warning:

“He (Paul) speaks about these things in all his letters in which there are some matters that are hard to understand. The untaught and unstable twist them to their own destruction, as they also do with the rest of the Scriptures.” (2 Peter 3:16)

Note that the Scriptural interpretation is not for the “unlearned” (untaught) nor for the “unstable” (dual minded inside) as Peter warns those who try to understand apostle Paul’s letters (according to the Wisdom which God has given to Paul).

Remember, the “most educated” apostle (Paul) is the one used by

God for the “exposition of Scripture”. Peter’s humility is evident when he admits to this truth. In short, God didn’t use the fisherman to expound the deeper matters of theology but rather the most educated man in His camp, Paul, at that time! (literally)

(Now, you too know the Secret of God. Believe!)