when in doubt about God?

And Jesus answering saith unto them, Have faith in God. For verily I say unto you, That whosoever shall say unto this mountain, Be thou removed, and be thou cast into the sea; and shall not doubt in his heart, but shall believe that those things which he saith shall come to pass: he shall have whatsoever he saith. Therefore I say unto you, What things soever ye desire, when you pray, believe that ye receive them, and ye shall have them.
Mark 11:22-24

BASIC CHRISTIANITY L1

SALVATION As a great building rest upon the structure of its foundation, so a church or the Christian life of an individual must be established upon a firm foundation. Jesus Christ is the Foundation, (I Cor. 3:11). Upon this Foundation one must build a structure based upon solid Bible truth. Let us begin our study with reviewing what happened to us when we trusted Christ as our Saviour and Lord.
“…. give diligence to make your calling and election sure …. ” (II Pet. 1:10).

The Holy Spirit

And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever;
Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you.
John 14:16, 17

Nevertheless I tell you the truth; It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you.
Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you thing: to come.
John 16:7, 13