Which sacrament is considered foundation of Christian life?

Answer 1

The Eucharist

Roman Catholic AnswerThat depends on what you mean by "foundation". The foundation of the Christian life would have to be Baptism, as, without Baptism, you can't receive any or the Sacraments or saving grace at all. Baptism, by itself, constitutes one a Christian in the eyes of God, and thus able to perform worthy acts.

Answer 2

Sacraments would be the requirements for salvation. Now denomination-ally those are said to vary - but what is known from the scripture is that you MUST believe that Christ is the Son of God. This is made clear over and over again:

Acts 16:29-31

29Then he called for a light, and sprang in, and came trembling, and fell down before Paul and Silas,

30And brought them out, and said, Sirs, what must I do to be saved?

31And they said, Believe on the Lord Jesus Christ, and thou shalt be saved, and thy house.

A sacrament is what you must do to be saved. No more no less.

Ephesians 1:12-1412That we should be to the praise of his glory, who first trusted in Christ.

13In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise,

14Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory.

Again it is the trusting in Christ that seals us. Until we are redeemed in Heaven.

I can only speak to The Bible as I know it and I read it - others might go back and forth about this or that. It is all very clear to me.

Another Answer:

Not all Christians have 'sacraments' to follow. You will not find any Scriptural teachings on 'sacraments' in the Bible. This is a man made tradition and is practiced primarily in mainstream churches.

Concerning 'Salvation,' the Scripture teaches this is God's plan for all mankind. (1 Timothy 2:4; 2 Peter 3:9), unwilling that any should perish. God's gift is eternal life through His Son, Jesus (Romans 6:23; John 10:9; 1 John 5:12).

What everyone must do is what Peter told the crowd on the 1st Pentecost:

Acts 2:38-39New King James Version (NKJV)

38 Then Peter said to them, "Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins; and you shall receive the gift of the Holy Spirit. 39 For the promise is to you and to your children, and to all who are afar off, as many as the Lord our God will call."

Answer 3

Catholic AnswerThe most blessed Eucharist is the Body and Blood, Soul and Divinity of Our Blessed Lord, Jesus Christ. It is the source and summit of the entire Christian life.

from The Catechism of the Catholic Church, second edition, English translation 1994

1324 The Eucharist is "the source and summit of the Christian life." (Lumen Gentium 11)" The other sacraments, and indeed all ecclesiastical ministries and works of the apostolate, are bound up with the Eucharist and are oriented toward it. For in the blessed Eucharist is contained the whole spiritual good of the Church, namely Christ himself, our Pasch." (Presbyterorum ordinis)

1325 "the Eucharist is the efficacious sign and sublime cause of that communion in the divine life and that unity of the People of God by which the church is kept in being. It is the culmination both of God's action sanctifying the world in Christ and of the worship men offer to Christ and through him to the Father in the Holy Spirit." (Congregation of Rites, instruction, Eucharisticum mysterium, 6)

1326 Finally, by the Eucharistic celebration we already unite ourselves with the heavenly liturgy and anticipate eternal life, when God will be all in all. (Cf. 1 Cor 15:28)