Yes, you can be a true Christian while struggling with doubts, as assurance is not of the essence of saving faith. While your heart may feel disquieted, you are never left without the sustaining presence of the Holy Spirit who keeps you from sinking into utter despair.
It is a common error to equate the absence of perfect assurance with the absence of faith. The clarifies that assurance is not of the essence of faith; true believers may wait long for it or find it weakened by temptations. The echoes this, noting that believers struggle with carnal doubts yet are preserved by God, who does not leave them to be tempted beyond their strength. As John Calvin observed in his , the faith of the believer is often a struggle against the very distrust that assails them, yet they remain anchored in Christ.
Scripture is remarkably honest about the reality of doubt among those who follow Jesus. Even at the Great Commission, when the disciples worshipped the resurrected Lord, records that 'some doubted.' Likewise, in , Jesus met Thomas in his specific demand for proof, addressing him with patience rather than condemnation. These examples demonstrate that the focus of our faith is not the perfection of our assurance, but the faithfulness of the Savior. We are called to look away from our own fluctuating emotions to Christ, who is the author and perfecter of our faith.