Is It a Sin to Question God?

As in calling him a liar certainly is. That will ensure you a place in eternal hell. 

Romans 3:4 KJV — God forbid: yea, let God be true, but every man a liar; as it is written, That thou mightest be justified in thy sayings, and mightest overcome when thou art judged.

No, it's not a sin

3 Questions People Would Like to Ask GodMany people are skeptical of religion and dissatisfied with its answers to life’s tough questions. But the Bible does have satisfying answers to questions people often ask

God created us in order to venerate him, to ask his forgiveness, obviously to make invocations to him by imploring him with insistence, such as to go to paradise.

Just talking about the God of the Bible. Very often faithful men of God have asked God questions, examples:

1.The faithful man Job: “Why is it that the wicked themselves keep living, have grown old, also have become superior in wealth?”​Job 21:7.

2.Jesus Christ: “My God, my God, why have you forsaken me?”​—Matthew 27:46.

3.The loyal prophet Habakkuk: “Why is it that you look on those dealing treacherously, that you keep silent when someone wicked swallows up someone more righteous than he is?”​ Habakkuk 1:13.

Read the context around these verses and you will never see that God is upset at these men for asking these questions.

Jesus told his disciples: “Keep on asking, and it will be given you.” (Matthew 7:7) The context of Jesus promise shows that he was talking about receiving not only material things but also answers to important questions.

Our Father Jehovah wants us to ask questions so we can get to understand him better.

No wonder his son Jesus in prayed to his Father said:

This means everlasting life, their coming to know you, the only true God, and the one whom you sent, Jesus Christ.

His position. Jehovah is the Supreme Sovereign of the universe, the King eternal. (Ps 68:20; Da 4:25, 35; Ac 4:24; 1Ti 1:17) The position of his throne is the ultimate for superiority. (Eze 1:4-28; Da 7:9-14; Re 4:1-8) He is the Majesty (Heb 1:3; 8:1), the Majestic God, the Majestic One. (1Sa 4:8; Isa 33:21) He is the Source of all life.—Job 33:4; Ps 36:9; Ac 17:24, 25.

Infinite, but approachable. The true God is infinite and beyond the mind of man fully to fathom. The creature could never hope to become equal to his Creator or understand all the workings of His mind. (Ro 11:33-36) But He can be found and approached, and He supplies his worshiper with all that is necessary for the worshiper’s welfare and happiness. (Ac 17:26, 27; Ps 145:16) He is ever at the zenith of his ability and willingness to give good gifts and presents to his creatures, as it is written: “Every good gift and every perfect present is from above, for it comes down from the Father of the celestial lights, and with him there is not a variation of the turning of the shadow.” (Jas 1:17) Jehovah always acts within his own righteous arrangements, doing all things on a legal basis. (Ro 3:4, 23-26) For this reason all of his creatures can have complete confidence in him, knowing that he always abides by the principles he establishes. He does not change (Mal 3:6), and there is no “variation” with him in the application of his principles. There is no partiality with him (De 10:17, 18; Ro 2:11), and it is impossible for him to lie.—Nu 23:16, 19; Tit 1:1, 2; Heb 6:17, 18.

His attributes. The true God is not omnipresent, for he is spoken of as having a location. (1Ki 8:49; Joh 16:28; Heb 9:24) His throne is in heaven. (Isa 66:1) He is all-powerful, being the Almighty God. (Ge 17:1; Re 16:14) “All things are naked and openly exposed to the eyes of him,” and he is “the One telling from the beginning the finale.” (Heb 4:13; Isa 46:10, 11; 1Sa 2:3) His power and knowledge extend everywhere, reaching every part of the universe.—2Ch 16:9; Ps 139:7-12; Am 9:2-4.

The true God is spirit, not flesh (Joh 4:24; 2Co 3:17), though he sometimes likens his attributes of sight, power, and so forth, to human faculties. Thus he speaks figuratively of his “arm” (Ex 6:6), his “eyes,” and his “ears” (Ps 34:15), and he points out that, since he is the Creator of human eyes and ears, he certainly can see and hear.—Ps 94:9.

Some of God’s primary attributes are love (1Jo 4:8), wisdom (Pr 2:6; Ro 11:33), justice (De 32:4; Lu 18:7, 8), and power (Job 37:23; Lu 1:35). He is a God of order and of peace. (1Co 14:33) He is completely holy, clean and pure (Isa 6:3; Hab 1:13; Re 4:8); happy (1Ti 1:11); and merciful (Ex 34:6; Lu 6:36). Many other qualities of his personality are described in the Scriptures.

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King James Version Bible

2 John Chapter 1

3. Grace be with you, mercy, [and] peace, from God the Father, and from the Lord Jesus Christ, the Son of the Father, in truth and love.

Ezekiel Chapter 20

3. Son of man, speak unto the elders of Israel, and say unto them, Thus saith the Lord GOD; Are ye come to enquire of me? As I live, saith the Lord GOD, I WILL NOT BE ENQUIRED OF BY YOU.

4. Wilt thou judge them, son of man, wilt thou judge them? cause them to know the abominations of their fathers:

Ezekiel Chapter 22

7. In thee have they set light by father and mother: in the midst of thee have they dealt by oppression with the stranger: in thee have they vexed the fatherless and the widow.

8. Thou hast despised mine holy things, and hast profaned my sabbaths.

9. In thee are men that carry tales to shed blood: and in thee they eat upon the mountains: in the midst of thee they commit lewdness.

10. In thee have they discovered their fathers' nakedness: in thee have they humbled her that was set apart for pollution.

11. And one hath committed abomination with his neighbour's wife; and another hath lewdly defiled his daughter in law; and another in thee hath humbled his sister, his father's daughter.

12. In thee have they taken gifts to shed blood; thou hast taken usury and increase, and thou hast greedily gained of thy neighbours by extortion, and hast forgotten me, saith the Lord GOD.

14. Can thine heart endure, or can thine hands be strong, in the days that I shall deal with thee? I the LORD have spoken it, and will do it.

Ezekiel Chapter 20

30. Wherefore say unto the house of Israel, Thus saith the Lord GOD; Are ye polluted after the manner of your fathers? and commit ye whoredom after their abominations?

31. For when ye offer your gifts, when ye make your sons to pass through the fire, ye pollute yourselves with all your idols, even unto this day: and shall I be enquired of by you, O house of Israel? As I live, saith the Lord GOD, I WILL NOT BE ENQUIRED OF BY YOU.

It's not a sin to ask God questions. The Bible is full of God-fearing believers doing that and God is gracious to them, helping them understand. But people on here don't seem to know the difference between asking God questions, and questioning God. A lawyer will question a person in court and the person has to answer. But God is the judge and He questions us! Read Job 38:1-3 & 40:1-14.

It would be...:

1. If a god existed

2. If it happened to be the Christian version of 'god'.

3. If sins were real things

4. If that particular version of the Christian god were overly-sensitive and triggered by implied criticism.

A better choice is to read Romans 11:31-33 to resolve any "question".

no since Gods do not exist in any rational mind outside of the religious mindset