If they were not necessary, God would not give them or permit them. The reason the for the Apostle Paul*s infirmities was a good one, that he might not be exalted above measure. We all have need of humility.
2 Peter 1:2: Grace and peace be multiplied unto you through the knowledge of God, and of Jesus our Lord, 3 According as his divine power hath given unto us all things that pertain unto life and godliness, through the knowledge of him that hath called us to glory and virtue: 4 Whereby are given unto us exceeding great and precious promises: that by these ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust.
2 Corinthians 11:30: If I must needs glory, I will glory of the things which concern mine infirmities.
2 Corinthians 12:7: And lest I should be exalted above measure through the abundance of the revelations, there was given to me a thorn in the flesh, the messenger of Satan to buffet me, lest I should be exalted above measure. 8 For this thing I besought the Lord thrice, that it might depart from me. 9 And he said unto me, My grace is sufficient for thee: for my strength is made perfect in weakness. Most gladly therefore will I rather glory in my infirmities, that the power of Christ may rest upon me. 10 Therefore I take pleasure in infirmities, in reproaches, in necessities, in persecutions, in distresses for Christ*s sake: for when I am weak, then am I strong.
James 4:6: But he giveth more grace. Wherefore he saith, God resisteth the proud, but giveth grace unto the humble.
1 Peter 5:5: Likewise, ye younger, submit yourselves unto the elder. Yea, all of you be subject one to another, and be clothed with humility: for God resisteth the proud, and giveth grace to the humble.
Evangelist Wil Rice:
You are saved by faith, so walk that way. What we do so many times after we come to Christ to save our souls is to attempt to strong-arm our way through our own problems. Friends, if God would give you His Son in order to secure your salvation, what is necessary for your salvation that God would begrudge? The answer is nothing!