There are many commandments, but they ALL hinge on these two commandments of LOVE:
25 ¶ And, behold, a certain lawyer stood up, and tempted him, saying, Master, what shall I do to inherit eternal life?
26 He said unto him, What is written in the law? how readest thou?
27 And he answering said, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy strength, and with all thy mind; and thy neighbour as thyself.
28 And he said unto him, Thou hast answered right: this do, and thou shalt live.
(New Testament | Matthew 22:37 - 40)
37 Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind.
38 This is the first and great commandment.
39 And the second is like unto it, Thou shalt love thy neighbour as thyself.
40 On these two commandments hang all the law and the prophets.
The promise is that if you keep these commandments will have eternal life. However there are more promises, here are some:
(Old Testament | Deuteronomy 5:10)
10 And shewing mercy unto thousands of them that love me and keep my commandments.
(New Testament | John 14:21 - 23)
21 He that hath my commandments, and keepeth them, he it is that loveth me: and he that loveth me shall be loved of my Father, and I will love him, and will manifest myself to him.
22 Judas saith unto him, not Iscariot, Lord, how is it that thou wilt manifest thyself unto us, and not unto the world?
23 Jesus answered and said unto him, If a man love me, he will keep my words: and my Father will love him, and we will come unto him, and make our abode with him.
(New Testament | John 14:15 - 16)
15 ¶ If ye love me, keep my commandments.
16 And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever;