Concerning Irresistible Grace, I once considered it (because it appears to be substantiated by 1 Corinthians 13:8a and Revelation 19:6).
If Irresistible Grace be the reality, then the ultimate conclusion is one of two things:
1) Limited Atonement
2) Universalism.
It is not Limited Atonement because of such verses as 1 Timothy 2:4, 1 Timothy 2:6, and 2 Peter 3:9.
It is not Universalism because of such verses as Matthew 13:41-42, Matthew 13:49-50, and Matthew 25:46.
So then, Irresistible Grace cannot be the reality.
What then of 1 Corinthians 13:8 and Revelation 19:6?
God, in His Omnipotent love, will not fail to give every man a free will choice as to whether he will receive Jesus as his Lord and Saviour and thus be saved unto the kingdom of heaven or else reject the Lordship of Jesus Christ and find themselves in the lake of fire after they have been judged as sinners without a Saviour.
For you see, in Limited Atonement, you have God choosing out people for heaven and hell apart from or against their will.
And in Universalism, man also does not have a choice as to whether he will obey or disobey.
And if it is not Limited Atonement or Universalism, how can Irresistible Grace be the reality?
Love never fails...
Therefore we think that love might never fail to apprehend the ones whom God desires to save.
But God desires to save everyone; and yet not everyone will be saved.
How then did God's love fail?
It didn't.
But God has chosen to give to every man a degree of sovereignty in his own right; so that he can choose whether he will surrender to the Lordship of Jesus Christ or rebel against that Lordship.
That choice will determine where he spends eternity.