Do the mentioned actions and statements—such as supplicating that God make one feel the truth of the Quran, or describing fate as foolish, or finding comfort in applying God's punishments (hudud), or repeating songs that contain oaths sworn by other than God, or doubting the nullification of Islam because of these actions—constitute apostasy or take their perpetrator out of the fold of Islam? And what are the consequences of that if the person is married? And is it obligatory to search and investigate one's past for actions that might have nullified Islam?

Your answer includes four points: 1. What was mentioned in your previous question is not apostasy and does not lead one out of the fold of Islam. 2. What you uttered was an unintentional mistake, so it is not apostasy, nor is there any sin upon you, for the Prophet, peace and blessings be upon him, said: "Indeed, Allah has pardoned for my nation mistakes, forgetfulness, and what they are coerced into." 3. The feeling you experienced due to ignorance does not lead one out of the fold of Islam and is not apostasy. 4. Swearing by other than Allah is not disbelief. You are not required to delve into your past, nor should you inform your wife about the matter, nor ask her to renew the marriage contract.

Regarding your last question: Your utterance of the two testimonies of faith with the intention of entering Islam is not necessary, as you did not leave the fold of Islam, and your marriage is valid. What occurred from you before puberty has no effect.