Spiritual world is not something that we can experience after death though I will not talk of supernatural things experienced by people while still alive or nearing death either by use of medium, or communication with those in the spirit world undertaken by the so called Spiritualist. These things like spiritualism are an abomination unto God the father.
Deut 18:10 There shall not be found among you any one that maketh his son or his daughter to pass through the fire, or that useth divination, or an observer of times, or an enchanter, or a witch,
Deut 18:11 Or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer.
Deut 18:12 For all that do these things are an abomination to the LORD: and because of these abominations the LORD thy God doth drive them out from before thee.
But we are not prohibited by the Scripture to look at the things which are not seen as they are eternal.
2 Cor 4:18 While we look not at the things which are seen, but at the things which are not seen: for the things which are seen are temporal; but the things which are not seen are eternal.
And this will be the basis of our faith. The things that will happen in the future – after judgment day, the life after death.
Heb 11:1 Now faith is the substance of things hoped for, the evidence of things not seen.
The world according to Scripture was framed by the word of God from things which are not seen not from the things that we now see.
Heb 11:3 Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which appeared.
I believe on Angels for they are introduced and talked about by the Scriptures.
Lk 15:10 Likewise, I say to you, There is joy in the presence of the angels of God over one sinner that repenteth.
While the Angels of the Lord are around us, the Angels of Satan are also around us waiting for us to commit mistakes.
Ps 34:7 The angel of the LORD encampeth around them that fear him, and delivereth them.
1 Pet 5:8 Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour:
How can a loving father, in his right mind, raped his 3 year old daughter and then chopped her to pieces to conceal his crime?
Eph 2:2 In which in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience:
How then can we resist that power within us? How can we separate ourselves from the children of disobedience?
Jas 4:7 Submit yourselves therefore to God. Resist the devil, and he will flee from you.
I can just but imagine the shame and the mockery made to the Angels of God and to God Himself when we commit mistakes or when wickedness triumph.
Rev 12:10 And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our God, and the power of his Christ: for the accuser of our brethren is cast down, who accused them before our God day and night.
Eccles 12:14 For God will bring every work into judgment, with every secret thing, whether it is good, or whether it is evil.