Using dispersion-corrected relativistic density functional theory, we have comprehensively explored the nature of Lewis acid-base interactions, providing a unified perspective on their bonding characteristics. Our findings reveal that these interactions span a continuum, encompassing both weaker van der Waals interactions at longer distances and stronger donoracceptor complexes at shorter distances. Importantly, all bonding motifs exhibit a covalent character, with the stability of the resulting complexes determined by the balance of attractive and repulsive forces. The covalent component (ΔEoi) determines whether a complex behaves as a strong or weak Lewis pair: When both the Lewis acid and base are strong, ΔEoi is sufficient to overcome strain, leading to a stable short-bond, donoracceptor complex. In contrast, when the Lewis acid and base are weak, the long-bond complex is formed where weaker forces, such as dispersion (ΔEdisp), become relatively important. This study highlights the versatility of Lewis acid-base interactions in molecular assembly and offers design principles to tailor these interactions.