Although the Bible never says, "Thou shalt not commit suicide," it does say "You shall not murder," (Exodus 20:13) and that would include self-murder. It also warns of a dire eternal fate for any who practice murder (Revelation 21:8 and 22:15).
Some think that since the suicides recorded in the Bible are not explicitly condemned, then suicide is allowed. The problem with that view is that it is clear from scripture that the people who killed themselves, such as Saul (I Samuel 31:4) and Judas (Matthew 27:5) were living outside God's will at the time of their deaths. They were not living in faith, and their deaths expressed a lack of hope in God.
Suicide and Sovereignty
This brings us to the main point, whether we're talking about suicide or assisted suicide. Suicide -- assisted or not -- is an expression of despair and/or an effort to wrest control out of God's hands. Christians believe in God's sovereignty -- that he is all-wise and all-powerful, and that life and death are best left in his care.
"The Lord kills, and makes alive;
He brings down to the grave, and brings up."
I Samuel 2:6
"Since his days are determined, the number of his months is with You;
You have appointed his limits so that he cannot pass."
Job 14:5
Not only is this 'best' but also right. It is an affront to God to take one's own life, both in consideration of his sovereignty, but also because murder is prohibited on the basis that it attempts to annihilate His image in man (Genesis 1:26,27). God requires the strongest punishment for murderers (Genesis 9:5-6).
Death and Eternity
Christians believe that when a person dies, he or she enters eternity.
It is appointed for men to die once, but after this the judgment.
Hebrews 9:27
One who is saved enters eternal life, one who is not saved is eternally damned.
"Most assuredly, I say to you, he who hears My word,
and believes in Him who sent me,
has everlasting life, and shall not come into judgment;
but has passed from death into life."
John 5:24
Thus, a Christian should never recommend, or help with, a suicide of an unsaved person because that would be hastening the unsaved person's damnation and prevent any chance of repentance. Does that mean that suicide is all right for a Christian, since he or she will enter glory? Well, no, for the above reasons, and for the following:
The Apostle Paul, in Philippians 1:20-24, expressed his sincere wish to die and be with Christ.
For to me to life is Christ, and to die is gain.
. . . I am hard pressed between the two,
having a desire to depart and be with Christ; which is far better.
Nevertheless to remain in the flesh is more needful for you.
He'd certainly had a rough life, and an early entrance into glory would have been a great relief. As the first missionary, who had brought many people to salvation, he could expect great rewards. Yet, he realized that he was needed on earth for the benefit of those whom he had brought to faith in Christ, so he would leave the timing of his death up to the sovereign Lord. (See John 21:20-23.)
Ultimate act of self-will
While you or I may not be able to imagine what could possibly be the reason for our remaining on earth, that decision is best left to God. This is one way we can live in faith. We also have the example of Job, who had lost everything - children, wealth, health, respect - and his wife thought he should curse God and die. She was basically suggesting suicide. But Job would not think of it. He was under incredible physical and emotional stress, for no apparent reason, but he refused to give in to despair.
"'Shall we indeed accept good from God, and shall we not accept adversity?"
In all this did not Job sin with his lips.
Job 2:10
Does a person's autonomy gives him or her the right to assisted suicide? In I Corinthians 6:19-20, the Bible says we (Christians) are not our own. We are bought with a price -- Jesus' blood. We belong to him, therefore we surrender our right to do as we wish with our bodies. We can and must use them to honor God.
Similarly, we have no right to involve another person in carrying out a 'death wish,' to carry out what is essentially murder (see Exodus 20:13). Assisted suicide means asking another person to take responsibility for your life, which you have no right to do. That is properly God's venue.
Challenge for God's people
Assisted suicide is a direct challenge for Christians. What can we do to prevent people from taking that drastic, irreversible step? One of the things that causes people to consider suicide is fear of being alone at the time of death. Christians are beginning to realize that we must come alongside people who are facing terminal illness, either by being with them right until the end, or by offering practical service to family members so that they can with with their loved one until the end. Baptists for Life has created a ministry called LIFT for just this reason. (See Matthew 25:34-40.)
True compassion
What do we need compassion for if not for moments when people are suffering? Compassion is best -- or perhaps only -- expressed in the event of another person's suffering. The word means "to suffer alongside" or to take another's problems on as one's own. Consider Acts 4:34-35 where the first believers had all things in common. If any were in need the rest didn't consider not sharing. There's also the admonition in James 2:15-16:
If a brother or sister is naked, and destitute of daily food,
and one of you says to them, "Depart in peace, be warmed and filled,"
but you do not give them the things which are needed for the body,
what does it profit?
These verses apply directly to the needs of the terminally ill and chronically debilitated.
Dignity or Grace?
Another fear people have is the loss of dignity, but is it possible for a person to lose dignity? Dignity is innate in the individual by virtue of his being made in God's image (Genesis 1:26,27). That can never be taken, or given, away. Like compassion, dignity is best -- or perhaps only -- expressed in the face of suffering. The greater the suffering, the greater the occasion for dignity, because, as the Apostle Paul found, we can glorify God in our suffering:
He said to me, "My grace is sufficient for you,
for My strength is made perfect in weakness."
Therefore most gladly I will rather boast in my infirmities,
that the power of Christ may rest upon me.
Therefore I take pleasure in my infirmities, in reproaches,
in needs, in persecutions, in distresses, for Christ's sake.
For when I am weak, than I am strong.
II Corinthians 12:9-10
Many people equate a loss of independence with a loss of dignity, however that is a Western (or American) invention. Christians grow as they minister to people who are vulnerable and dependent. Likewise, it requires a special grace to be the one helped. There is no shame in being served. Both experiences are needed in a person's life, and in the life of the Church.
If suffering induces loss of dignity, then that would mean Jesus Christ himself lost dignity on the cross. On the contrary, he is our greatest example of endurance and source of comfort:
For we do not have a High Priest who cannot sympathize with our weaknesses,
but was in all points tempted as we are, yet without sin.
Let us therefore come boldly to the throne of grace,
that we may obtain mercy and find grace to help in time of need.
Hebrews 4:15-16
Related: Pro-life Bible studies