We know that the whole creation groaneth and travaileth in pain together. (Rm 8:22)
Suffering is the way in this world of death, decay and destruction. Think about all the ways people are suffering right now. Think about all the ways animals are suffering right now. Think about all the fighting, arguing, anger, hatred and wars going on right now, all over the world. Think about the suffering: physical, mental, emotional and spiritual.
We suffer because we are living in Satan's evil world of death. Satan is "the god of this world." (2Cor 4:4) People suffer because of Satan and his evil soul within them: because sin reigns in the souls of men, "the imagination of a man's heart is evil from his youth" (Gen 8:21) We reap what we sow because the whole world lieth in wickedness. (Gal 6:7-9, 1James 5:19)
Every one is tempted by his or her own soul. Every one is tempted by Satan, "who walks about as a roaring lion, seeking whom he may devour." (1Pet 5:8) Satan is the ruler of the bottomless pit; down here he IS god. Satan's name in the Hebrew language is Adadden, which means, "the one who exterminates and destroys." Satan is the devil and he has the power of death. (Rev 9:11, Acts 2:14)
God does not allow suffering. God is Love. Suffering is a part of this creation; built into the design of this evil creation of Satan's. "An eye for an eye, and a tooth for a tooth, vengeance is mine saith Satan. I will have blood sacrifice!"
"Let no man say when he is tempted, I am tempted of God: for God cannot be tempted with evil, neither tempteth he any man with evil." (James 1:13) God is Good.
We are currently trapped in this world of Satan's, who boldly claims, "I am the LORD, and there is no one else; there is no God besides me. I create the evil." (Isaiah 45:7)
The Living God of Love and Life is not here in Satan's world of hatred and death. That is why God sent the prophets into this world. That is why God sent Jesus into this world. That is why God sends the angels into this world. God is not here in this bottomless pit which He created to hold Satan and his followers who rebelled in heaven. That is why we are not in heaven. That is why we are here - Understand?
We live here, trapped in Satan's world of evil. If we believe in God, and try to live a righteous life, we suffer: as it is written, "we cease from sin, we suffer in the flesh." (1Pet 4:1) If we don't believe in God, we suffer in our ignorance, because we are all God's children and Satan hates God.
It is because we ARE the children of God that if we sin, we suffer; and it is because we are the children of God that if we cease to sin, we suffer in this world of Satan's. In this world we are dammed if we do, and dammed if we don't. However, "it is better to suffer for doing well, than for evil doing." (1Pet 3:17) Evil doing keeps us here in the world of pain and suffering. Righteousness takes us out of here and back home to Life in heaven.