For all have sinned, and come short of the glory of God; Romans 3:23
Why do we need Jesus? When you understand that we have all fallen short and are sinners, then you will understand that we need Jesus. There is nobody who has walked the planet that hasn’t sinned, except Jesus (1 Peter 2:22)
And since the wages of our sins equal death (Romans 6:23) there is no possibility of eternal life without Jesus. Jesus is the only way to eternal life and God (John 14:6) This is why Jesus had to die on the cross, Jesus took on our death for us (Hebrews 2:9)
So is Sin from God? No , God doesn’t know sin because he is Holy (James 1:13), all Sin comes from Satan and is a rebellious act against God (1 John 3:4). This is why Sin can’t be tolerated in the Kingdom of God, for the wages of sin is death, but God is eternal.
However, there are consequences for sin, Adam and Eve were immortal (Genesis 2)but introduced sin and death into the world due to their rebellion against God (Genesis 3)
So Jesus became the ransom for our sins (1 Timothy 2:6) He took on the sins of the world so we can be made pure again in the eyes of God. (Isaiah 1:18) Without Jesus there is no ransom, there is no life.
Jesus is the resurrection and the life (John 11:25) We have victory over sin and death because Jesus conquered them at the cross (Revelation 21:4), this is why You Need Jesus