Christianity is both a vertical and a horizontal relationship. It is a vertical relationship of the believer with God; and, it is a horizontal relationship of a believer with other believers who are also a part of the body of Christ. This horizontal relationship is transacted within a local context in which God places the believer. Below are the ten priorities and purposes for a local church in which the believer is a vital participant…

The Biblical constitution of a local church:

¶ Let love be genuine. Abhor what is evil; hold fast to what is good.
Love one another with brotherly affection. Outdo one another in showing honour.
Do not be slothful in zeal, be fervent in spirit, serve the Lord.
Rejoice in hope, be patient in tribulation, be constant in prayer.
Contribute to the needs of the saints and seek to show hospitality.
¶ Bless those who persecute you; bless and do not curse them.
Rejoice with those who rejoice, weep with those who weep.
Live in harmony with one another. Do not be haughty, but associate with the lowly.
Never be wise in your own sight.
Repay no one evil for evil, but give thought to do what is honourable in the sight of all.
If possible, so far as it depends on you, live peaceably with all.
Beloved, never avenge yourselves, but leave it to the wrath of God, for it is written,
“Vengeance is mine, I will repay, says the Lord.”
To the contrary, “if your enemy is hungry, feed him; if he is thirsty,
give him something to drink; for by so doing you will heap burning coals on his head.”
Do not be overcome by evil, but overcome evil with good.
ROMANS 12:9-21

The Ordinance of Water baptism:

¶ What shall we say then? Are we to continue in sin that grace may abound?
By no means! How can we who died to sin still live in it?
Do you not know that all of us who have been baptized into Christ Jesus
were baptized into His death?
We were buried therefore with him by baptism into death, in order that,
just as Christ was raised from the dead by the glory of the Father,
we too might walk in newness of life. ¶ For if we have been united with Him in a death like His,
we shall certainly be united with Him in a resurrection like His.
We know that our old self was crucified with Him in order that the body of sin
might be brought to nothing, so that we would no longer be enslaved to sin.
ROMANS 6:1-6

The Ordinance of Water baptism admits believers into the status of being admitted to ‘the Lord’s Table’:

You cannot drink the cup of the Lord and the cup of demons.
You cannot partake of the table of the Lord and the table of demons.
First Corinthians 10:21

The Ordinance of Holy Communion:

When you come together, it is not the Lord’s supper that you eat.
For in eating, each one goes ahead with His own meal.
One goes hungry, another gets drunk. What! Do you not have houses to eat and drink in?
Or do you despise the church of God and humiliate those who have nothing?
What shall I say to you? Shall I commend you in this? No, I will not.
¶ For I received from the Lord what I also delivered to you,
that the Lord Jesus on the night when He was betrayed took bread,
and when He had given thanks, he broke it, and said,
“This is My body, which is for you. Do this in remembrance of Me.”
In the same way also He took the cup, after supper, saying,
“This cup is the new covenant in My blood.
Do this, as often as you drink it, in remembrance of Me.”
For as often as you eat this bread and drink the cup,
you proclaim the Lord’s death until He comes.
¶ Whoever, therefore, eats the bread or drinks the cup of the Lord
in an unworthy manner will be guilty concerning the body and blood of the Lord.
Let a person examine himself, then, and so eat of the bread and drink of the cup.
For anyone who eats and drinks without discerning the body eats and drinks judgment on himself.
First Corinthians 11:21-29