What is the meaning of believe? In this it is to fully know without doubt and full trust that He is and His promises to us are a surety.
Ga 3:22 But the scripture hath concluded all under sin, that the promise by faith of Jesus Christ might be given to them that believe
Notice there are two things the Saints keep !
Re 14:12 Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.
Eph 2:8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
Eph 2:9 Not of works, lest any man should boast.
To have faith and believe and trust fully one must know that He is who and what He says He is. Do You?
Heb 11:6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.
Mt 17:20 And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.
Do we need help to increase our faith? I for one know so and the apostles also.
Lu 17:5 And the apostles said unto the Lord, Increase our faith.
Lu 17:6 And the Lord said, If ye had faith as a grain of mustard seed, ye might say unto this sycamine tree, Be thou plucked up by the root, and be thou planted in the sea; and it should obey you.
Mt 15:28 Then Jesus answered and said unto her, O woman, great is thy faith: be it unto thee even as thou wilt. And her daughter was made whole from that very hour.
We are not strong enough in faith and trust and knowing for a surety who He is and trusting without a shadow of doubt. We are too unsure and unstable.
Heb 10:23 Let us hold fast the profession of our faith without wavering; (for he is faithful that promised;)
Jas 1:6 But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed.
Know that His promises are sure, that His every Word is true and will not fail in the least.
All should read the Faith Chapter, Heb. Chapter 11: often.